TMPGEnc, properly known as Tsunami MPEG Encoder, is an MPEG video and audio encoder for Windows, written by Hiroyuki Hori.
It is very easy to use. I noticed it's pretty cool compared to bbMPEG, because it's also very fast (optimized for the newest processors if so desired) and has just as good video quality.
The program is freeware, but the MPEG-2 encoding is time limited. (It's still very good for VideoCD production...)
Home page: http://www.tmpgenc.com/