First Gen iPod wont take movies.

I try and upload movies to my 32gb 1st gen but after the sync they are not there. The sync takes a while like they're trying to go on but when I start the iPod there are no movies. The movies I am trying to upload are digital copies from Blurays and also some DVDs that I converted. I have done it before with this iPod but now it isnt working. Any suggestions?