Both are worth it if you want everything and plan to play it, both aren't if you just want to cherry pick the best.
On Valve Pack. Everything in that pack other than Portal 2 can be attained for 5$ or less during sales. It may take a bit to collect since they do flip around. But for what its worth; Half Life, Half Life 2+Episodes, L4D2, CS:S or CS(Which ever one you prefer), and Portal. Multiple times, Portal has been given away for free, while the other ones during sales would run you about 15-20$ combined. Wait till Christmas, 10$ Portal 2. Wait till next summer, probably around 5-7$.
Paradox Pack. Same thing applies as the Valve pack, but I'd say this one has more fluff.
For example, you don't need Mount and Blade at all. Just Warband, and most seem to say hold off on Sword and Fire till a few more patches. Do you also need too strategy titles like Hearts of Iron and EUIII at the same time? Be difficult to play both of them.
If you know you'll like what is in each pack and will play it. Go for it. If not, then just wait for another sale and cherry pick each one.