If you join the CT team, make sure you buy a TMP instead of an MP5, because:
A) It's cheaper
B) It's a much better killer because
B1) It's near-soundless, and no muzzle flash
B2) Headshots are so godd@amn easy to achieve with it.
Practice for a few rounds, and you'll rock ass.
If you have a Scout, it's very easy to just go scouting (
) around the map, zooming and sniping, or just plain running and firing. The Scout doesn't lose any accuracy (enough to make a difference) when you are running, so take aim at their chest, fire, rebolt, aim slightly to the direction they were moving in, and fire.
However, the AWP only lets you fire semi-accurately while walking, not running.
The AK47 is indeed less accurate, but it's still a good weapon, considering the price. IMHO, the SIG Commando, is much better than the Steyr AUG, because it's got super-low recoil while zoomed, a little better accuracy while unzoomed, and for me I kinda feel lighter using it.
Last, if you're a rushing-type person, shotguns, SMGs, and rifles are your type of thing. IMHO, the PARA is only good for close-medium range, firing in bursts of about 5 bullets each.