Actually AFAIK the Tab key used in command prompt is configurable (in XP at least).
The easiest way to do this is to download TweakUI from Microsoft's PowerToys (
link[
^]) pack and change the "Filename completion" under "Command Prompt" to whatever. Hope this helps!
UPDATE:
For Windows 7 you can give this
Tutorial[
^] a try.
Apparently the tab key can be disabled either by registry (for all instances of cmd.exe or by using:
cmd.exe /F:ON
or
cmd.exe /F:OFF
I'm still on XP so you need to test that yourself. Let me know how it goes!