Depends what game it is.
Haven't played too much COD, but when I do it's just gung-ho with whatever shotgun I manage to pick on the inventory list.
On Battlefield, I generally go for ninja-soldier with a shotgun and explosives, mostly knifing people (or shotgunning them if they notice me) and placing c4 on enemy vehicles in their base, then detonating them when they get on. Even better if there's heaps of them around.
In Unreal Tournament, I just run and gun with whatever weapon's handy (even the bio-rifle). But sometimes I prefer to sit down and snipe for a couple of minutes.
In Team Fortress 2 I frequently use the Scout or Heavy in serious games, but in less serious ones i'll go Demoknight or Huntsman-Sniper (because i'm useless with his actual snipers).
Last edited by 4zb41; Oct 6, 2011 at 08:21 AM.