To install mpeg2enc, download mjpegtools from http://sourceforge.net/project/showfiles.php?group_id=5776&package_id=5823 and build it. mpeg2enc is included there.
Here is an example for downloading, unpacking, compiling, linking and installing it with SUSE Linux 11.3:
yast -i libjpeg-devel
- download the source
- unpack it