AL: I haven't been on this forum for awhile,so straight away your post drew Me in. You see I was thinking I was going to see yet another Burnt-out Rouge-Mod stepping outta line,but after reading this thread from top to bottom I can't see how You could think anyone was outta line but you!
I mean here was a N00B asking how to accomplish video playback & the guys who answered him were 100% dead-on,not a single doubt about that.
Now I'll grant you that the codec packs mentioned aren't recommended by the power user's over at Afterdawn or Doom9 as to be the best to install on Windows since they have been known to cause problems with the OS & besides they're Bloat-ware.
But seeings how the poster is new to Compression/Decompression & playback of .avi files,any 1 of the codec packs mentioned would have suited his needs perfectly.

Codecs are used to compress videos for ease of storage & transport size. Once the file is relocated onto a medium like a dvd-5/9 or another hard drive it is then once again via Codecs decompressed for playback by the player(MPC or VLC). It's not the player that Compresses & Decompresses the avi but rather it's the Codec's job to do that for the player so that the player can then do it's job & play the file.
You don't have a clue as to what makes a video(avi.file) play or not! and how You could post on this forum & act like you do is beyond Me, I mean what were You thinking Dude? "A Codec will help it's what makes them play"
Your very first post in this thread was tainted with cynicism, Straight Up Dude You're Wrong On All Points!

All I install for "playback of My DVD's & almost all My video files" is ffdshow & MPC & then I if I need another codec then & only then do I install it.
Because as I understand it,for one to install all those codecs in one fell swoop is asking for trouble.
Anyway I don't know most of the mods here except the one's who've helped Me out aprox a year ago(you know who you are) but I can say he knew what I didn't & I'm sure all the Mods do or they wouldn't be Mods!
Keep Up the Good Work Guys.