deleting temp cd/rw files

xp pro: i set up some "files ready to be written
to the cd" (it's a cd/rw). now if i change my mind and
try to delete them from the staging area, using "delete
temporary files" or any of the other delete options, i
can't do it. i get a msg saying the files are in use.
(they're not.) if i re-boot xp, then i can delete them.
this wastes a lot of time if i'm trying to organize files
to write to the cd/rw. is this a bug? is there a fix?
can't find ANYTHING about this on google or in msft kb.
many thanks.