Is your batch daemon running?
Assuming it is, go to Admin Console->Batch Process Control and input an entry ID. It will show all the jobs related to that entry ID which will give us some pointers as to where the process is stuck.
If your batch daemon is not running, try to start it with:
# service kaltura-batch start
and look at the log /opt/kaltura/log/kaltura_batch.log to see whether it starts correctly or generates errors. If there are errors, post them here.