Well from your description it looks like there is a delay when windows is looking for your drives.
Do you have an XP CD ?
If so put the CD in the drive,then go to START - RUN type SFC /SCANNOW in the RUN box. It should check and replace any damaged system files.
Alternatively you can boot with the XP CD and do a REPAIR INSTALL this will overwrite all the windows files but leave all your data and programs intact.