How can I crop VOBs before I burn them?

[eterna111]

Sometimes I borrow make backup of my DVDs (with DVD Decrypter) and then burn them. If they are too big, I transcode them with Nero Recode, which usually gives really good results.

But sometimes I get movies that look like this:
http://img207.imageshack.us/img207/4642/dvd01original9ie.jpg (http://imageshack.us)

And what I want is a tool to crop the empty spaces, so it becomes like this:
http://img207.imageshack.us/img207/6438/dvd02cropped4zv.jpg (http://imageshack.us)

Any idea about any tools that can do this (not too complex, hopefully :D) would be appreciated.

Thanks!

[MarcN]

As far as I know only 720x576, 704x576, 352x576 and 352x288 are valid resolutions for a PAL-DVD. You can get rid of the the black bars on the left/right and reduce the once at the top/bottom by croping and resizing the picture. But you have to re-encode the video for that.