To my understanding, and I could be wrong, your settings would be saved on your FE or computer, not the server. There is probably a file or folder you could delete to get back to default settings although I'm not sure which ones do that. It has to be some type of cfg file.
I just checked, there is a mouse.cfg file which might be it.
I'd save that as a backup, say change it to mousebackup.cfg and see if the game creates a new default mouse.cfg file. I'm assuming it will.
I also believe no decision has been made on mouse usage in AH2... yet.
Would any settings for the mouse in your OS effect the way it reacts in AH1 or 2 is a good questions that HTC would have more info on.