Easier. Create a boot disk and get into DOS. Go to your C: drive and type "ren windows winold". Then go into "c:\winold\option\cabs" (might be "c:\winold\options\install") and type setup.exe and hit enter, and it will pretty much do a clean install of windows without having to delete anything. Once you're back in windows you can go into the winold folder and copy over shit you might have left in there, like c:\windows\desktop.
So, get into DOS, type "c:", hit enter. Type "ren windows winold", hit enter. Type "cd winold\options\cabs" or "cd \winold\options\install", hit enter. Or "cd winold", enter. "cd options", enter. "cd cabs", enter. Then type "setup.exe", enter. Then just walk through the setup.
You can download a boot disk here:
http://bootdisk.com/bootdisk.htm. It will make it onto a floppy.