hey, dom, i think i no how to fix this, goto Start Menu, All Programs, Accessories, System Tools, Disk Cleanup
then press OK
then it should say summit like 'Calculating disk space'
then in the list that pops up, select all of them apart from 'Compress Old Files' then press OK
i hope helps, it used to bug me when i had XP Pro, never happened to me with XP Home tho