Hi,
Try a Optical Mouse from Logitech or Microsoft. Both can be had now for under 20 bucks. I just bought a Microsoft Two button Optical Wheel Mouse from Best Buy in Southcenter Washington for under 20 bucks. It can be used in ps/2 mode or usb mode. Also make sure your running the latest driver which is 3.2 off microsofts website (under devices).

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Some of the good things in life are free!