Shooting production or limited is really a personal choice; you are only shooting against like equipped shooters so it doesn't gain you any advantage. Shooting minor in limited would be a disadvantage.
I shoot production and always bring six mags and carry one more than the number of reloads I'll need for a particular stage in case I have to rip a mag out because of a jam. Nothing's worse than running out of ammo before running out of targets.
Maximum number of rounds for a stage is 32. They should have told you the minimum number of rounds for the match. Paper targets usually require two hits, but can be any number. You can shoot more than that unless the stage is Virginia count, which means no more rounds per target than they tell you. There will probably be some steel targets. If you miss one steel more than once, slow down and hit it.
The rules are posted on the USPSA website; read them. Breaking a safety rule at any time can earn you a DQ (match disqualification), so don't go faster than you can go safely. Once the timer goes off you will only notice the targets and forget anything you told yourself to do/not do.
Despite my warnings, it's a whole lot of fun.
