Anyone have time machine "lock up" while backing up and not completing the task?

I have the drive connected for over 24 hrs and time machine will only back up 25% of the 75Gb it claims to need to back up.

I have re tried and get the same result, and T.M. will show "backing up" even after 24 hrs.

I know it is not the drive being too full or being defective, since a partition set up for a pc works just fine.