Hockey 101
Part 1: Forwards
On defense
Just because forwards are known mostly for scoring does not mean they don't need to worry about defense as well. The basic defense setup reflects a basic offense setup. That is, the offense will have defense at each of the points (the area where the blue line meets the boards) and their forwards down low (closer to the net). Therefore, our LW and RW should generally be covering the defense, while the center should hang out around the slot (the area between the 2 faceoff circles right in front of the net) and cover anyone who may get open in that area.
This link shows the basic zone defense Use your stick to get in the passing lanes and take away options for the other team. The other job for forwards on defense is to get open and give the defensemen passing options when they do recover the puck. If you see the other team's defense pinching (that is, cheating towards our net) you may be able to sneak behind them and receive a long breakout pass for a breakaway. Generally, though, "cherrypicking" isn't the best plan unless we're behind toward the end of the game, and not playing defense might upset your teammates.
Breaking out
Once we have recovered the puck and are moving out of our zone, there are a few options. The first is to move onto offense by passing and skating into the zone. This is fairly straightforward and involves forwards getting open and not going offsides (as long as one of your feet is behind the line you're ok). If you're looking for a pass and trying to get open, keep moving. Maintaining your momentum will make you harder to cover and when you do get a pass it's easier to turn and go than to start from a standstill.
Here is a standard breakout.
The other option for transitioning is playing dump and chase. You can use this if the other team's defense is playing aggressively. All you have to do is flip the puck into an offensive corner (wait until you're over the redline or it will be icing). Then chase after the puck and the defenseman who is also going after it. Since he's probably closer he may beat you to it, so you can get the puck back by either playing his stick (lift or poke check) or his body (check the crap out of him). If one of your teammates decides to dump and chase, you can help him out by either covering the other defenseman (who is the most likely passing option if D1 recovers the puck) or by also going after the puck and backing up your teammate.
Here is a standard dump and chase.
Offense
Cycling is good. Cycling is where the three forwards form a triangle and pass the puck amongst themselves. Cycling is good because the puck-carrier has at least 2 passing options (more if a defenseman is open) and can also shoot. I have a feeling that other teams will try to doubleteam (at least) the puck-carrier. If you are being doubleteamed, that means that someone else is wide open. If you have have the puck, try to find that person. If you don't, try to be that person.
Here is the cycle. You should look for the following qualities when you want to shoot: 1) In front of the net. 2) Closer is generally better. 3) You don't want anyone in front of you. One exception to #3 is deflections (you don't want to be RIGHT in front of the shot. The general area is fine). If you don't have the puck and your teammate has a good shooting chance, GET TO THE NET. This will allow you to attempt to deflect the puck (your player will do this automatically), and will also allow you to pickup a rebound and shoot on the out of position goalie. The other team's defense does not want you to be in front of their net. They will check you. You can check them back. Battle for position.
Forechecking
Eventually we will lose the puck. This is where forechecking comes in. Forechecking is where one or more forwards harass the other team and try to get them to lose the puck. Much like defensive zone play, this can be done with your stick or body. Forechecking is important, but so is getting back on defense. Generally one or two of the forwards will forecheck, while the rest of the team falls back. If you are a forward and see two of your teammates forechecking, you probably want to get back so the other team doesn't get an odd-man rush.
Here is a two player forecheck. Notice the other winger is playing back with the defensemen. This is known as a Left Wing Lock. There will not be a test.
Hockey 101
Part 2: Defensemen
Defense
The main goal of defense is pretty obvious: get the puck from the other team. Sound positional play, however, can make it very difficult for the other team to score even if they have the puck for most of the game. Therefore, a good defenseman doesn't take himself out of position to make the huge check. That's how breakaways happen.
Here's the zone defense again. As you can see, the d-man's territory is generally the lower half of the ice, from the front of the goal to the corner. It is the defense's job to go into the corners after the puck. As on d-man does this, it is the other's job to cover the front of the net. Lots of goals are scored by an uncovered player in the slot while the defense gets caught behind the net.
In addition to getting the puck and playing positionally, there are a couple more jobs you'll have. The first is clearing out the front of the net. Many offensive players make a living in front of the net, hoping to deflect a puck, get a rebound, or at least screen the goalie's vision. You need to stop them legally. You can push them around with the right stick, but if you do it too much you may get a crosschecking or interference penalty. Another option is lifting the stick, preventing them from making the shot.
Blocking shots is also important. The problem is since d-men play close to the goal, sometimes they can block a shot and actually end up deflecting it into the goal! They also could be screening the goalie's vision. This should not stop you from trying, but the further you are from the goal the less likely this will happen, and the more time the goalie will have to react if it does. BUT DON'T MOVE TOO FAR OUT OF POSITION.
Breakout
Once you have recovered the puck, the next step is going on the offensive. Most of the time this involves passing to a forward. Look where you are passing. If your breakout pass gets intercepted you are right back where you started, and probably not in a very good defensive position. Take the time to make a smart pass. Your defensive partner should back you up and provide you with another passing option, such as behind the goal. Once you made the pass, you probably don't want to rush up with the forwards. Hang back a little and see the play develop. Often rushes will stall in the neutral zone and you will want to be in position to go the other way quickly. Once the puck is safe in the other half, proceed to the offensive zone.
Offense
The normal position for a d-man on offense is at the point (see other Hockey 101 post). This will allow you to keep the puck in the offensive zone on many clearing attempts. If the play is mostly occuring on the other side of the ice, you may want to cheat a little toward the middle to provide a better passing option. However, you don't want to stray so far that you won't make it back to the point to keep a puck in. If you get the puck, you can pass, shoot, or dump it into a corner for your forwards. Be careful, when passing from D to D; these passes can be intercepted and taken the other way very quickly. Point shots can be a valuable tool, especially if you have a clear shooting lane and your forwards can set up by the net. An important part of offensive d-play is knowing when to go after the puck and knowing when to play it safe and retreat. These instincts will come with practice, but if you're not sure it's probably better to play it safe at first rather than give up a breakaway from the red line.
Defensive Rushes
So your forwards gave up the puck, and your defensive partner was way out of position. Now you're on the receiving end of a 2 on 1. What do you do? Don't panic, just stay with the play and watch it develop. Skate backwards ahead of the other team. Generally the idea is to take away the passing options and let the goalie deal with the shot. You can do this by blocking the pass with your stick, laying down (this will make you completely out of position if you miss), of playing the receiver's stick.
Here's an example of a 2 on 1. The D in this example actually played the puckcarrier a little more than the passer. In time you'll figure out what works.