I would try the following four things, but there can be risks and I don't accept liability, however it has worked for me. So first BACKUP if you can't afford risks.
Then:
*1 Turn off system restore: Right click on my computer, system properties, performance, filesystem and tick Disable System Restore.
*2 I also boot up on a Dos floppy of windows 98 and cd to C:\_Restore\ temp\del *.* and delete everything
C:\_Restore\ archive\ del *.* and delete everything
Some of these can take a very long time as there could be gigabites of old backups.
* I would go Start, Run, msconfig and enter, chose startup and disable office, and any other applications you don't need running all the time
leave the antivuruses and important applications as scanreg etc. You can tell by the paths which are normal applications which you can start when you need them.
Then it will ask you to restart, and crossing my fingers I would go for it!
When it comes up tick not to show it is a test startup, as you will want it to be permanent if it works.
*4 Then if you have a Norton Disk Doctor you could also try running Windoctor and fixing everything automatically.
With this you might be ok, or you might chose to restore your backup who knows? Best of Luck!
David