Actions Games: (eg, Arkham Asylum): Sneak attacks, usually by hanging them upside down. I really hated it when they started putting bombs on the gargoyles and introduced snipers. I know difficulty curve is important, but you took away a lot of my stalking spots.
([Prototype]): Imitating a guard and then stealthily eating every guard one at a time until only I remained. Again, difficulty curve eventually fucked up stealth portions in this game which pissed me off because I preferred stealthing it up over going in and wrecking shit up.
RPGS: (Pokemon): I guess I'll just say I like hitting Rockets with the BIGGEST attack I have in my arsenal. Whatever I have. Infernape's Close Combat. Heracross' Megahorn. Whatever. But I think I just love kicking ass with a Gyarados/Electivire combo. Wins almost every time.
(Neverwinter 2): Um... didn't get far in this, tbh. But I always liked talking out of situations if I could. Not because I didn't like combat. But to conserve health for the bigger battles I know I'd need. Just a preference.
FPS: (L4D): Sniping, Magnum, Katana, or Guitar. All of these are amazingly awesome tools for surviving the hordes. I like molotov's too... but, honestly, nothing is better than listening to the tune you play while beating a Tank to death with a guitar (note, there isn't really a tune unless you are as crazy as I am).