Please Help Anyone!! iTunes/QuickTime problem

Hiya.

Please could someone help me?

I recently had problems getting audio from AVI movies[i just got a clicking stungun effect type sound] and I was only able to fix this problem but System Restoring back a week. This took me to the day when i had updated iTunes.

Before I did the System restore iTunes was working ok playing music. Now it won't start up - keeps saying there is a problem and it has to shutdown. I tried undoing the restore but that not only returned the AVI problem but didn't fix anything either.

I have uninstalled and re-installed iTunes 4 times and had no luck. Now QuickTime wont install or uninstall every time i get this message:

quote

Error Number: 0x80040707
DLL function call crashed: OTInstallcode.QuickTimeUninstallProc

Please can someone help me as I only know one way to fix it which is Formatting the Computer but i have done that 8times in the last year due to various problems and my sanity can't take doing it again.

PLEASE HELP