http://www.fpsbanana.com/tuts/5173" onclick="window.open(this.href);return false;
Basically this fix gives you true widescreen when playing CoD4. I am using this and its sensational. It took me a map round or two to get used to it but its great.
open your config_mp.cfg configuration file.
Which is located in your DRIVE:/Program Files/Activision/Call of Duty 4 - Modern Warfare/Players/Profiles/YOURNAME folder.
This is not a cheat, exploit, or whatever... it just fixes your display to be true widescreen when in game.Open the file in Wordpad; and hit CTRL+F, and type in cg_fov.
Hit "Find next", it should go straight to the line that says seta cg_fov "65".
Simply change the 65 to 80, save the file and your done.