Syncing issues and couple other issues with phone iPhone 3G

Ive always had no problem syncing the phone to iTunes. Now for some reason I cant add or sync my music to the phone. When I connect it, it reads the phone, backs it up, but as soon as it starts to sync the phone goes away on the box on the left in itunes and the screen on the phone says sync in progress for as long as I leave it plugged in.
I get a series of 3 error messages saying the device cant be synced cause the disk cant be read/written to. Along those lines.
I can sync photos, calender info, address book contacts. etc. Just stops syncing as soon as I try syncing the music. I even was able to delete all the songs off of it.
Is there a seperate disk for the music that might be damaged? Would a restore fix this you think?
Of lesser importance I cant get the switch from silent to ring to go back to ring, the phone still rings, only goes on silent when you slightly move it from the bottom up a little. So the phone is ringing but that little switch will not move.
I dropped the phone friday night from a counter top and the sim popped out. I put it back in and it seemed fine right after that. Could this maybe be the problem?
Thanks
Powerbook Mac OS X (10.5.7) iPhone 3G