There is a privacy eraser in the software called Registry Cleaner Expert. I know it works under win 7... I clicked on it thinking it was just a cleanup program and it ran for 10 minutes.. overwriting every thing that had ever been deleted about 10 or 20 times.
If you simply want to prevent someone from undeleting files that have been emptied from your recycle bin.. usually a defrag will destroy the ability to simply undelete.
Eraser is an advanced security tool for Windows which allows you to completely remove sensitive data from your hard drive by overwriting it several times with carefully selected patterns. Works with Windows 98, ME, NT, 2000, XP, Vista, Windows Server 2003 and Server 2008.
This is a bit late, but as I came across the post while looking for a 'right clickable' file eraser I thought I might as well point you towards RightDelete 1.3. It is very small and does exactly what it says it will in the blurb. I also tried File Shredder 2.0 as I'd used it before but it would register in the context menu of Windows 7 x64. Cheers.