My copy of Alien Resurrection is starting to have some issues, Alien 3 too but at least with that one it's just the odd audio glitches.
When I watch the special edition, parts of the theatrical opening credits are in the special version and also at the end, it cuts off part of the dialogue and the shot of Paris and just goes straight to the credits, it's annoying but not too bad, I guess I'll have to face the fact that one day I might put it in the DVD player and it'll say :"No Disc".