crawl is basically the easiest to jump into roguelike out there, using the hardcore opinion that dredmor isn't even a roguelike because it lacked a few key features on release that made me hate it
pointless rant at dredmor:
(the control scheme was slow as piss and if you ever observe another player playing crawl on the server which btw is something you can do! so yes teams can actually play together chat and help each other make choices and check each other's exact scenario... anyways...yeah people on the crawl server play at warp speed something you couldn't do when dredmor first came out, I heard they patched it but meh)
crawl's design philosophy is that if something is unintituive and stupid it gets removed from the game, that's why EXP dancing was removed (you don't need to know what that is) it's very possible to play crawl poorly, it's a very hard game, but it's quite easy to learn the interface, the skill comes from learning what choices to make and how to decide, and what strategies are most effective where... there are 102893102910 things you need to know to win, but only 1or2 things you need to know to start playing and having fun!
when I made it to the final level in the crawl .9 tournament and was within sight of the orb of zot I got a ton of advice from people in chat/forums and they made that advice by actually looking at my game screen! so they could give great advice, although the majority of the advice was, oh dude you're fucked you shouldn't've let so many of your resources get destroyed on the 2nd to last level before you contacted us for advice! (I fought quite a lot of draconians even though i probably should've just ignored them all with what build I had going I didn't realize exactly how unavoidable and huge a drain on my resources orbs of fire would be, and how also high a drain on resources for no reward and easy to avoid draconians were on the late game levels, that's one great thing about crawl, every death should teach a life long lesson, an obscure life long lesson that will almost never come up again!)
that's one reason I'm really hoping to get added to a bay12 team, one reason I get turned off by crawl is that well... sometimes I'm entirely stuck, halfway or 3/4ths of the way or so into the game, I get to a portion of the game I'm no longer experienced at (I'm not good so most of my experiences are playing the first half of the game over and over) and having someone to ask to take a look... well it can be nice, especially if they're self motivated to take a look because if I do better on that playthrough they get clan points too!~
if I don't get put on a team I'll play in the .12 tournament and maybe be smart enough to practice a bit beforehand :-p
TL;DR crawl is VERY EASY TO GET INTO I've taught 9yr old girls to play (they didn't play that well but still that speaks to the concepts and interface!) crawl is a very deep game with a very simple interface, it's fun right away!