DVDs will not play

[kaiser_man]

When I put in a DVD into my G4 imac running 10.4.7 the DVD player fires up fine, it will ask me the usual questions when it starts up. Then a few things will happen:

1. If I choose 'last time played' DVD player will crash after about 2 minutes.
2. If I choose 'start at beginning of disc' the menu of the DVD will play but if I try to play movie from the menu it will not work, but it will play if I go to scene selection and choose the first scene.
3. If I choose anything other than the first scene it will more offen than not crash the DVD player.
4. If I manage to get the film to play it pauses every 45 seconds or so for about a minute then eventually will crash again.
5. This may or may not be a related issue, I cannot burn CDs on my Mac anymore but I can burn DVDs, CDs play fine on it too.

I have played this DVD on my Mac before, and I have just tested the DVD on my PC and it works fine. I am finding it is doing this on most of my DVDs now.

I have deleted my prefs which made no difference, has anyone got any ideas? Help me please, it is driving me mad!

[Satcomer]

Well you could try to reset your PRAM. If that doesn't work then it maybe time to replace the DVD drive because they can go bad.

[kaiser_man]

I will try that now, if I have to replace the DVD drive again I think I will be getting myself a new mac