I just picked up my new bike [see here!] and riding it home with the chain on the biggest front sprocket it was rubbing against the front changer... now I know there are two little screws on there to adjust this, but what do I gotta do to sort it out?
For starters, since it's new, remember that your shop should be glad to fix the bug for you and will be annoyed if you fiddle with the screws and then fall back on them The screws simply act as stops to limit how far the cable can move the derailleur's cage in and out, so they are actually a set-once-and-leave-alone thing, like the idle-speed limiter on a carbuerator. It's more likely to be the alignment and/or cable adjustment.
If you'd like a full rundown on adjusting a front derailleur, check out Park Tool's guide to FD adjustment. I also posted some troubleshooting ideas in a thread here. But as I say, your shop should be happy to de-bug this for you. BTW, I read your other thread, glad to see you finally have a nice bike again!
Scott Gambler, Scott Ransom, Kona Bear, Bianchi 928 Carbon/Chorus, C'Dale Rize4
Another thing to consider, when in the biggest chain ring try not to have the chain on the lowest gear (largest cog) on the back. It will can cause the chain to rub the front derailer and put undo stress on the chain. If you are running the biggest cog on the rear use either the granny gear or the middle chain ring.