Vista and XP Pro Encryption

I had encrypted my old C: on an Averetec (POS company) I finally had to get a ACER due to the above ing out on me.

I have removed the old drive and made it a USB drive which will not boot on the ACER so the easy fix of loading XP PRO and then unencrypting the drives contents is a wash.

Now the ACER has Vista home premium (yeah sucks I can not revert it back to XP Pro thru the MS trade up program since it is not Ultimate (Per Acer).

I want to get my Thunderbird mail off the drive and a few other documents but I am running into permission issues. I can not get Vista to take ownership of the entire drive or the files I want either.

Can some one give me a sure fire way to get access remove the encryption and get ownership so I can get my files back.

Next I will want to add these to the email folder on Vista and have them usable… Ideas?

Thanks