I've found Super from Erightsoft simple and very good for all kinds of codec conversion and compression etc.
"If you need a simple, yet very efficient tool to convert (encode) or play any Multimedia file, without reading manuals or spending long hours training, then SUPER © is all you need.
It is a Multimedia Encoder and a Multimedia Player, easy-to-use with 1 simple click.
SUPER © is totally FREE to download and to use.
It plays & converts very fast full length movies to any other format without any time or function limitation.
NO trial or evaluation version of SUPER © but one unique fully working version.
SUPER © does NOT require any additional external codec to be installed, absolutely nothing. Necessary codecs are built in!
SUPER © can also play and save Internet Media Streams with different protocols ( mms:// rtsp:// http://)"