Stick with the SMGs (sub machine guns) or assault rifles to start off with. Overall those 2 groups of guns are the best and easiest to use.
I like Kill Confirmed. It's like Team Deathmatch only you get points for your team by picking up the dog tags of the player you killed. Other teammates can pick them up, or the opposing team can pick them up and deny you the points.
Don't spend a token on:
sensor grenades, the 2nd available shotgun, the shield, Swarm scorestreak (you won't reach it)
Spend a token on:
Counter-UAV, Ghost (your last one), every assault rifle and SMG (so you get a feel for them and find which gun suits you best,) the 2nd launcher
Also, is there a goEMAW PSN/Xbox live thread already? Regardless, I'm on the PS3 so if you wanna add me send me a PM and I'll send you one back.