My main weapon is my knife, I nearly have 4000 knife kills according to my Battle log.
Setups.
Assault: M416, AEK-971, F2000, Famas and G3A3, all with foregrip\heavy barrel
Engineer: A-91, M4A1 with foregrip and heavy barrel.
Support: C4 for tanks, Claymores in small maps... I don't use the heavy guns, so I stick with SMG's... PP-19, P90 and PDW.
Only time I use the recon is when I'm camping and spawning team mates in the enemies base.
Favorite guns are the shotties by far, USAS before the patch was my favorite... now I use the DAO, mostly.
Favorite handguns: 1911 w/ suppressor, Magnum, REX, just got the 93r tonight and had A LOT of fun with it.