I found that the directions in the V+ menu worked with no problems. Make sure you plug the scart into the bottom scart socket on the V+ labelled VCR/DVD rather than the top socket. Obvious when you know but very frustrating when you don't and your recordings won't download.
The instructions are also in the V+ manual. Here's where you can read it if you don't have a copy.
http://www.virginmedia.com/customers/pdf/V+Manual.pdf
I don't see why your DVD wouldn't work in another player, guess you would just need to try it and see.