ok so i got doom
Do you mean you got it working in widescreen? Remember, just delete the FOV line in the config file. You don't need it. Use "0" for 4:3, "1" for 16:9 and "2" for 16:10 screens in the "aspectRatio" line and you'll be golden. You still need the other three changes as well: mode -1, customwidth and customheight.
I don't have the expansion pack for Doom 3.
Call of Duty requires similar changes, but there is no "aspectRatio" entry. For that game you must specify the FOV you want. For a 16:9 screen the exact value is 96.418343. See this post if you have a 16:10 ratio screen.
http://htpcnews.com/forums/index.php?showtopic=8444
You may want to also change this line in the config file: seta com_introplayed "0". Change the 0 to a 1. Otherwise you'll watch a blank screen while the intoductory videos play. "1" prevents the videos from running.
Keep in mind however that the FOV hack only works in the single player config. If you try changing the FOV in the multiplayer config, it always reverts to 80.