Asking this question on a predominantly US forum is not going to get you accurate answers.

Best way to get into beer is to head to a UK beer festival and start drinking at random.
That said, I will endorse a few select recommendations made here:
I'm not a huge stout drinker, but I try them once in a while and this was definitely one of the more pleasant ones. Plenty of other good beers from Youngs as well.
Hoegardeen
With a slice of lemon. Spent far too long working in Holland, which meant that I had to drink either Heineken or Hoegaarden. And so I picked up a taste for Hoegaarden.
Or, if they didn't have any in, this tended to be the alternative.
The local off license when I lived in Edinburgh put in a lot of work to get some of the best US beers shipped over to Scotland, and the Flying Dog beers stood head and shoulders above the rest. I may still be dismissive of US beers in general, but it's thanks to Flying Dog that I no longer entirely mean it.
Newcastle brown ale crops up a lot in these threads - it's my beer of choice in pubs that don't sell decent beer on tap, because you can pretty much always rely on them having a bottle or two in the fridge, but it's more of an old reliable option than anything special.
A few other recommendations of my own: anything from the Badger brewery is a good start. Tanglefoot has been the beer that converted any number of my cider and lager drinking friends and relatives to the real stuff, and Fursty Ferret is another extremely quaffable pint, but Golden Glory (peach blossom flavoured) and Blandford Fly (a beer with a hint of ginger) are nice oddities as well. And speaking of oddly flavoured beers, Fraoch (heather) and Grozet (gooseberry) were a couple of very pleasant beers I got to know up in Scotland, though I couldn't tell you the brewery and have never seen them on tap.
Fullers' Golden Pride is an incredible beer I've discovered recently. It's a deceptively drinkable golden ale but it's a moderately stunning 8.5%. Sure, there are stronger beers, but they mostly taste like it, and some of them you could use to surface roads. This stuff is delicious and light but still hits you in the back of the skull like a hammer.
If you ever get the chance to try Innis and Gunn beer then jump at it. "Vanilla, toffee and orange aromas, with a malty, lightly oaked, lemon and chocolate palate. Deftly balanced and light in texture, soothing and warm in the finish." Or so they say, and I can't argue with that. The oak finishing process really does make for a unique taste, though personally I prefer the standard stuff to the limited edition.
For UK-dwellers, a pleasant surprise is the Co-Op own brand range of beers. They're actually brewed by big name breweries and repackaged for Co-Op, with a slightly more budget supermarket price.

The organic ale is particularly good, which it shares with quite a few other organic beers - the Caledonian brewery does a particularly good one.
And I'll leave you with one of the more peculiar beers I ever had the pleasure of tasting. Stonehenge Ales' somewhat incredible Sign of Spring. It's a very smooth seasonal beer with a light and... well, spring-like flavour to it.
Oh, and it's green.