Yeah DVD decrypter+IFOedit+some form of burning software works great once you learn what you need to do...and their are plenty of guides available.
Alternative number 2 would be to purchase DVDXcopy which is really starting to mature nicely. I personally picked up a copy of DVDXCopy because I just started getting lazy
Still though, a few dvds, especially older ones, will not work correctly with DVDXcopy so it pays to know how to do it the manual way no matter what. Not only will it help you to fully understand how a DVD movie works, but it does come in handy from time to time.