Deleting Vista files from inside XP to facilitate clean setup

I had Vista installed in a dual boot configuration when I decided to install a newer build of Vista. (Going from beta to to build 5472)

However, because of bad experiences by others, I wanted to do a clean reinstall. The drive containing Vista also contained other files, so I did not want to format the Vista drive.

So I thought I would simply go into XP, and delete the Vista Windows directory by hand. This turned out not to be as simple as I thought because I was getting Access Denied or depending on the method getting 'the file is in use' on the files.

After trying several options I found out this is the way to do it:

1. The vista files are owned by an unknown SID (from the Vista installation). SO the first thing to do is to use the Advanced button on the security dialog of the directory to take Ownership.
2. Go to the permissions tab, and make your Owner get full control of the directory, and make sure that you:
   1. Do Not inherit permissions from the parent directory
   2. Do make contained files & folder inherit from this directory

This way you have made sure that you new owner can access all vista files & folders with a Full Control permission set, and you be able to delete the files