OK - I fixed the DVD recording - The first time I accepted the default name - I changed the filenames to ones without spaces (I used hyphens) and did some more and they work fine.
NOTE: the editing of the name when you select rip is non-intuitive. You can only use the backspace key to edit it, plus auto repeat (holding down the backspace key) doesn't work.
I tried ripping a few more DVD's accepting the default name, and they worked.
It seems I was just having a problem with the first rip (watch out for that) and thought it was a space in the filename issue, but turns out it wasn't, after all.