Nero Backup causing movies go jerky

I made a total backup of all my computer content a while ago before re-installing the win xp home system. Today I restored the backup files but the movies now go jerky, un-smoothe. Is it possible to fix this or are they destroyed?
I have the Nero 7 ultra edition.

Sounds more like you have a different codec / filter installed. Does this happen in all players? Have you tried VLC, this doesn’t use Directshow. Are the files still jerky when played in there…? Is you hard disk running in PIO mode instead of UDMA?