Avidemux for this dummy

[Gettinit]

Hello.  I am a plumber and have some sewer video's to put together.  Normally I just have a short video to present but I had a large industrial building that I had to map out.  Dummy me, I did it while I was sick and never used the pause button trying to push through and get out faster so I need this program.  I just downloaded it and I need to get AVI files and MP4 files onto the program.  Ultimately from there I need to edit each file and put them together into hopefully one coherent video.  The reason for the two different formats were two different cameras.  At the moment I need to know how to get them all into the program, order them and start editing.  After that I would like to put at least the AVI's and MP4's together.   

[Gettinit]

in case it matters I have the 2.6 64 bit version.

[Gettinit]

Found the Wiki quick start.  That helps a little.  Can I edit out the voice over?  Can I add in voice over?  Can I add in text?  Pointers?  I am off to bed.  Thanks in advance.

[AQUAR]

I think the very first step is to download mediainfo and find out what video compression format is used inside the avi and mp4 files.
http://sourceforge.net/projects/mediainfo/files/

[Gettinit]

Downloaded.  Now I need to know how to use it,