Add me as I'm just getting started on this too, looking for a squad that just doesn't run in all directions.... play mostly as support, so a medic and a couple of assult noobs - i play on conquest 64 mostly, just keep getting flags, supplying loads of ammo and laying claymores all over the place.....
had many a comedy death, so if you don't mind me laughing down my mic feel free to add me
A lot can depend on how you fire. Generally you should only go full auto (holding R2) on enemies at close range. Anything over medium or longe range, you really ought to use burst fire. You have to remember that weapon recoil and bullet spread can have a big effect, so if your holding down R2 in a long salvo at a target 200 metres away, you're really not gonna hit much.
Have you tried adjusting the sensitivity to see if it helps with aiming? I think its set at 20 but I usually ramp it up some to make aiming and movement easier.
BF always take time to get used to. Especially if you are used to the arcadey feel of COD. My best advice would be go through the Assault class/medic and actually play the game properly. There is nothing more frustrating then dying then finding out you had a ally medic near by that chose not to revive you. Also spot enemies when you see them in the open so they then appear on the mini map. For doing this you will also get a small amount of points and when you do reach level 17 plus every point counts because the ranking up process really does start to slow down.
The starting weapons are not any worse than any other gun they don't get better with rank like cod, the best engineer gun on battlefield 3 was the M4A1 before they nurfed it and you started with that gun. They are just different.
When you get the hang of killing don't just play sniper or assault when you need to take down enemy vehicles at range, try and always play the objective and what is best for the squad/team, don't just revive someone who has just been gunned down without first killing the assailant. try to be aware of people round you so you don't just run in their way, DON'T STAND IN DOORWAYS. Don't spawn on your silent sniper/player (who is allowing the squad to spawn in but keep hidden)and start blasting away with a really loud gun to give their position away.
Played the objective and stick with your squad.