DVD skips/freezes at the end of movie

[29ways]

This has been happenning recently to all my movie backups(all on ritek 4x dvds). Just started happening a couple days ago. On some DVD players it will skip before the end of the movie, on mine it only skips within the credits. Something I also noticed was the playback would darkened then lighten. Besides that, I would try to copy the backup back to my hard drive with dvd decrypter and it would give me a read error on the last vob its copying. I recently bought a new motherboard and cpu but I'm pretty sure the problem occurred before the switch. Please, anyone, help! I'd appreciate it.

sony dru-500a firmware 1.0d(went from 2.0e to 1.0g back to 1.0d)
can only burn 4x ritek with 1.0d
Using dvd decyptor and Nero 5.5.10.15 now the new .20

[LIGHTNING UK!]

Well my ritek 4x burn at 4x with 2.0e firmware.
My guess is your discs arent up to much.
Burning to fast for the media often ends up with discs that skip towards the end.

[29ways]

Been burning at 4x for a couple months now. Never had a problem with playback until now. I've also been using the ritek brand but maybe it is time to move on to a different brand.

OH! and by the way, I also did a 2x burn on ritek, which ended up with the same skipping results. Just wanted to know if anyone had any solutions. I just might format all my partitions.