Flash drives and iPod no longer recognized in My Computer

My PC runs Windows XP SP3. Starting a week ago, it stopped recognizing my flash drives (both Sony Microvault and SanDisk Cruzer micro) and my iPod. I have several external harddrives and it recognizes all of them just fine. My Device Manager indicates that the flash drives and iPod are working fine, but indicates that the drivers for them are disk.sys, drvmcdb.sys and PartMgr.sys! When I try to use Update Driver to set up the correct drivers, I get a message that the "current" incorrect drivers are the best ones and it won't change them! My Sandisk flash drive is password protected. It always lights up when I plug it in, and sometimes it says "initializing drive" but it never actually does and in a minute or so the light goes out on the drive.
I'm pretty computer savvy, but this has me stumped. This may help: the problems started after I uninstalled a windows xp update called desktop indexer (or something like that). One day this application appeared in the lower right hand corner of my desktop, blocking out the quick-start icons. I had never asked for the application and had no use for it so I uninstalled it using the uninstaller from the Control Panel.

I have stuff I really need on the flash drives. I actually spent like 40 dollars for a driver update application that didn't help at all. Please -- HELP!!!