I bought a McAfee job-lot "bundle" about 2 years ago and part of it was "Diskclean" which allows me to "delete" or "shred" anything that is in the Trash folder. On it's own they charge £25 for Diskclean so maybe not a good idea, I'm not sure if there's anything about that's free like freeware or shareware. Have a look on
www.download.com there may be something there to help.