I can't say much about D&D, having not played for a while, and being from Ireland. Now I can only pop round to Other Realms on North Main Street (I think) sometimes during the summer and play their Assault On Corkonia Warhammer thing, which is thrilling good fun, really.
(Other Realms is the only shop for geek stuff in Ireland, pretty much, they have a branch in Limerick as well, and they're extremely thorough. I once saw a Penny Arcade poster, a Hollis Mason as Nite Owl action figure, copies of the most famous graphic novels ever made, and the biggest collection of tabletop stuff you will ever see in Ireland in about 5 seconds looking around.)
There I go again on my regular customer sprees. (They're also an internet café with loadsa MMOs installed, but I've never used their computers, so I can't say much about speeds)
Seriously, stop me now.
Anyway, the best thing to do is find some reasonably priced books, a decent campaign, because it's hard as a brass monkey's bollocks on a cold day (too graphic?) to create your own campaign on the first go. One that's any good, that is. Anyway, don't tie yourself down to asking about one game, I know people who would murder you for touching their Call of Cthulhu stuff. We are talking about fanatic devotion.
D&D is the classic though, and pretty easy to pick up, as I discovered during one of my early sessions. I would have kept playing and devoured any game-defying crap the Dungeon Master sent our way. Mostly because I love crazy stuff to spice up the story. I once went through an entire campaign as a talking frog, which I was turned into (using Frog, and a permanency spell, I'll come to the talking better later) at the end of our last campaign by our arch nemesis, a thousand-year-old and immensely powerful warrior magician known as the Shadow Paladin in some circles, maybe. During that campaign, I enjoyed being the funny character a lot. A key game mechanic in that quest to turn me back to my true form (which climaxed in me being turned into a sort of morph-into-anything GOD for a period nearing the end of a final battle with the now undead Paladin of Darkness, who had been dabbling in the Necronomic arts.) was to use me to generally freak people out, get into houses covertly through a window or something and steal the key to something or other, that sort of thing. I also negotiated and tricked creatures of all sorts using that awesome tongues effect, which was the result of us using a Wish or Miracle or something to as for my return to Elven form, and the god (DM) refusing, (because it would break the campaign) because we had a great destiny ahead on our current quest, but taking pity on me and giving me the gift of speech in every language and tongue instead.
Just one of the crazy things that can happen to your party while you're playing D&D.