For generic SMG, the SMG in Half Life 2. Fuck the Gravity Gun...I had the SMG!
For generic pistol, the one in Halo: Reach (which is basically the one from Halo 1).
For generic sniper, the Fareye from Resistance. No fancy bullets, just a handy time slowing mechanic.
For generic shotgun, the Doom shotgun. Not the Super Shotgun, the basic one.
For generic assault rifle, the Blaster (Yellow gun base form) from Jak 2/3.