First, I assume you're NOT talking about COMMERCIALLY released DVD's?
I'd suggest the best place to start is over at
www.videohelp.com and/or
afterdawn.com. Videohelp has some very nice tutorials on all things
related to DVD burning, cloning, backup, etc.
If you're talking about COMMERCIAL DVD's that have copy-protection, etc
[illegal, unless perhaps for "own personal use," "backup," etc.] that's
a job for the freeware combo DVD Decrypter & DVD Shrink. You'll find
more info on both at above sites. Of course, these utils will work on
your "home video movies" as well.
Remember, too, that you not only have to convert NTSC to PAL, but may
have to deal with Region Codes as well if the DVD's are commercial. The
above freeware combo will help you there.
In terms of shareware, you just can't beat the Slysoft combo: AnyDVD &
CloneDVD.
www.slysoft.com
After you rip your DVD to your hard disk, there's a very neat trick
that works maybe 90% of the time. It's using a freeware tool, IFOEdit,
which simply helps you edit your IFO files now on your hard disk by
simply inserting PAL codes to replace the NTSC once. It doesn't always
work, so it's a good idea to use rewriteables to try. Again, excellent
tutorial at videohelp.com.
There's a whole slew of freeware tools to do exactly what you want.
Remember, that you'll need lots of hard disk space [a typical DVD has
just under 5 gigs] and it'll be a memory-intensive process to
rip/convert. [Some freeware tools can require as much s four times that
for processing and creating temporary files.
Remember, too, that if all you want is the video on your hard disk and
not necessarily burned to DVD, you can use freeware tools to rip the
DVD to your hard disk and then several other freeware tools to convert
the files to, say, AVI, MPEG, etc. format, which will obviously take up
considerably less hard disk space.