I'm a roll player, not a role player. I drop points into the Diplomacy skill so that I don't have to be a diplomat in real life. I like "unlocking" plot points & secrets. I'm typically the guy keeping track of enemies, spies, & allies. I like taking revenge on those that elude me the first time around. I prefer the "harder" and/or "support" characters, such as the bard & cleric. I like to play by the rules -- some homebrew is OK, but weird crap that allows players to have 100 AC and do 50000 points of damage makes things meaningless, so exclude me from that junk.
I think games that are 3 or 4 hours are too short, and games that are 8+ hours are too long. I'm in my 30s, so playing with people who are in their 40s, 30s, or late 20s feels right.
I play D&D 3.5 edition. I use d20srd.org usually for free access to the rules. I would be OK trying a True20 game, a d20 game, or a Pathfinder game, as they're all variants.