Looks pretty decent.
Here's what I'm using currently
The best feature is the ability to disable negative acceleration and fine tune the mouse settings per Foot/Vehicle/Chopper/Free View seperately.
Other good features is the Restore to Defaults button, the fact it has a few more features, and the overall clean and well organised interface.
Perhaps you could *ahem* borrow a few ideas?
What I like about yours is the ability to see the settings.ini directly inside the program and (I assume) see/make changes directly. What I don't like about yours is the picture in the background makes it a bit too busy IMHO. The graphics tab, with the picture minus the tank and more off to one side looks better in my opinion. What I'd like to see, personally, (if you haven't already) is that when you select an option or change an option, it should highlight that line in the settings.ini window, so you can flip pages and see how your changes are applied directly.