I don't need to do that, swrain. I was following the disk and cpu usage using the System Monitor and the only thing active in the disk-thrashing cycle was Avast. Besides, the idea of booting without AV in place gives me the screaming meemies.
The fact that the only thing active being avastSvc.exe (File System Shield) isn't entirely correct as the avastSvc.exe doesn't just scanning for no reason as it is an on-access scanner, so something is opening files, etc. causing avast to scan them.
The trick is trying to find what is responsible for that activity.
Some considerable time ago, my firewall also had an anti-spyware module, if that was enables that literally touched hundreds of files and that cause avast to scan the files it was opening.
In your case if the FSS is only scanning 140 files during boot, that is darn low and shouldn't be giving your hard disk a thrashing. Do you happen to have the winXP indexing service running as that can be responsible for a lot of HD activity ?
Another area is MS Office if you have that, the Fast Find is another one that can give your HD a workout.