Simply deleting them should solve the problem. Most Internet browsers has an option to let you block 3rd party cookies. Firefox: Tools -> Options -> Privacy -> Uncheck "Accept third-party cookies"; Internet Explorer: Tools -> Internet Options -> Privacy -> Advanced -> tick "Override automatic cookie handling" -> tick "Block" in "Third-party Cookies".
Also you can set which website's cookies are be blocked.
Yeah I've done all that lol
Didn't help... Nothing seems to block them >.<
And I'd block the website if I knew which one it was sending them lol
YOu could try using Killbox! to kill whatever file you want. Just use the delete temporary files options provided by this software and make sure the delete cookies is maked. Run it on the default use and any other users you want. Usually works for me. It has even got the option to delete specific files after a reboot if all else fails.