Well without knowing what the reg file did, this is just a rough guess. Below is the bog-standard mouse settings for the registry:-
Copy and Paste the info between the lines and save it somewhere as NormalMouse.reg then just double-click it.
------------------Begin Copy and Paste------------
Windows Registry Editor Version 5.00
If your refering to my post, then it does nothing other than return an altered mouse configuration back to the default settings. If your refering to the XPMOUSEFIX.reg, then I have no idea, I haven't seen it.
It's supposed to get rid of the built in mouse acceleration in xp. It's used for fps games like half life, counter-strike since mouse acceleration messes up the aim of most people who were used to playing in windows 98.
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS