transcode OMG to AVI?

[josefnpat]

Ok, I am entirely new to the linix command line. (Ubuntu 7.04)
My linixbox has VLC and FFMPEG installed (Using the Add/Remove Applications tool), and I have no idea how to correctly trans code the data. The wizard does not trans code anything that works for me. I tried using the command line, but alas, makes no sense. I figured out how to get a sh script running, but I can't get it to do anything. Could someone please write me a quick shell script that would do the following?:

Input: "/home/user/Desktop/input.ogm" OGM, Audio Track: "Track 2" Subtitles Track: "Track 1"
Output: "/home/user/Desktop/output.avi" H263, width: 320 height: 240

I honestly have no idea how to code this. Thanks in advance.