Removing C:\undo\backup.cab files

I just upgraded from Windows ME to XP Pro, ( clean install ) everything is running very smooth. My question is about C:\undo\backup.cab files I heard these are files that are left over from Windows ME can they be deleted safely. Every time I run Defrag it seems like it takes for ever when Defrag is scanning C:\undo\backup.cab files,do I really need them.
I do not plan on going back to Windows ME.
If so are they easy to delete.

HP 800
XP Pro
768 mb Ram

 

gday night just found this elsewhere hope it helps http://www.tomshardware.com/forum/20879-45-backup-delete

 

Thanks,I found the same thing but does any of the Majorgeek senior members have anything to say about it.