I "play" casually. In that I have cards, quite a few, but rarely have time to actually play. I also have a bad habit of buying cards every now and then. I bought a booster box of the latest core set this past summer and have yet to play a game using cards from it, although I do have a fun looking tourney legal soldier deck rearing to go. Well actually it probably isn't tourney legal anymore because of some older cards I bought for it.
My favorites are the duel decks. Love buying two that are just ready to go, have some good strategy to them. Knights vs. Dragons, Azani vs. Nicol Bolas, I like buying those from time to time.
Casually I have a fun white/black knights deck and a red/green Dragon deck that is tons of fun when it draws right.
Very fun game, good luck as you get into it. I find that playing MTG is a lot like gaming online. It often depends on the people you are playing with. There are jerks, trolls, people who take it way too seriously and then there are others who are really fun to hang around. Hope you get a good group.
My next MTG project is to make mono-color EDH (commander) decks, since the last core set released some amazing mono color legendary creatures. Some day I'll make the time...some day...