MeD's Movie Manager is a simple to use, yet customizable, movie manager. Info is automatically retrieved from IMDb and tv.com.
Technical info can also be retrieved from media files like AVI, OGM, MPEG and DVD (ifo). It's written in Java and should therefore run on most desktop systems supporting Java.
MeD's Movie Manager is a free software distributed under the GPLv2 or later license, you may download binaries and source code for no cost at all.