I wouldn't recommend using them, just their codecs.
I think powerdvd has better audio codecs and windvd has better video codecs, or is it the other way round?
Anyway my recommmendation is install both and use neither, Zoomplayer has the ability to steal components from other players, so you can perfectly emulate the performance of powerdvd with better functionality and lower resource usage.
Infact if you get zoomplayer packaged with lots of filters, you only need zoomplayer. What you do is go to the DVD section under options and you can then pick and match what playback filters you want to use, then register them and those will be what zoomplayer uses.
I can't recommend doing this more highly, given that powerdvd and winddvd natively aren't great, even if there playback filters are.
So that's a thumbs down to using powerdvd natively, that's a thumbs up to stealing powerdvds filters and using zoomplayer to playback
