Deleting Locked Folders Or Files?

Using explorer to search through the temp internet folders, I find there are
a few files that are not being deleted. About 30 of them are named
"size=1x1&name=ATAtracker..etc.etc..gif" at 1KB in size. In another folder
also under the Temporary Internet Files | Content.IE5, is a file
"makeplaylist.dll%3F....etc.etc..asx". In another folder 2 files from a
Playstation 2 website both filenames starting with
"Network=ugo&size=....etc.etc..html". There are more folders yet, but this
serves as enough. The right click on the filename does not render the
delete option. Depressing the keyboard delete button does not cause the
file to delete nor even bring up the confirmation window for deleting.
Trying to delete the folder(s) themselves, even in Safe Mode brings up a
message saying "Cannot delete Size_1~1.gif. Cannot find the specified file.
Make sure you specify the correct path and filename." In folder attributes,
there is the read only option to check or uncheck.