If the file is overwritten it is not recoverable.
But that's not your goal. You want the DIRECTORY entry to be overwritten.
http://eraser.heidi.ie/trac/ticket/54 notes they considered that to be a bug worth fixing.
I will not vet, vouch for Eraser but I see what you are asking even though I'd not worry about the directory entries.
I would like to know how to delete files from my Vista computer and then prevent file recovery programs from being able to see them.
I don't want the file names to appear in any file recovery programs.
I have tried a few applications here on CNET downloads that delete/shred unused file space. They have not worked.
I have tried copying a folder with large paint files to fill up my hard drive to overwrite everything. That hasn't worked.
I use Recuva. It still lists files that I have deleted/shredded/written over.
How can I delete these file names from appearing?
Recuva has a right-click option supposedly overwrite these files, but their names still appear.