VideoLAN is probably most used player nowadays. It has a feature which is worth highlighting.
This program supports many formats, among them MPEG, VCD, SVCD, VOB, AVI and DVD. Moreover, you will be able to execute files from a local network of the Web by streaming.
With VideoLAN you can do different things to the visual files, such as: reduce the reproduction speed, choose your favourite section in each movie, add subtitles and much more.
It has a very complete and easy to use interface; therefore, you will not need additional knowledge about similar applications.
VideoLAN is the most efficient alternative to reproduce the videos you have on your PC.