Ok, first off, that really sucks, I should have perhaps said that I used this for windows xp? Windows seven wasn't out at that time so I didn't think to do it.
Secondly, if anything, I'm guessing its the -heapsize command that might have messed with his tf2. If I were him, I would delete the D:\Program Files\Steam\steamapps\HISUSERNAME\team fortress 2\tf folder, just the TF folder, and then trying to boot up tf2 again.
Also, if he hasn't done so, to take out the boot commands. If he just wants the window mode, tell him to only type -novid -noborder and then to go into tf2 and select the WINDOW option in the video tab (assuming he can actually boot tf2 after doing the prior step).
If that doesn't work, it might have to do with Windows 7, and since I'm still on xp, I don't know if I can offer much help on that.
Lolwut?