Hey RB, I hava a cheap ($8.00 usd on ebay) Logitech wireless mouse, and only use NiMH recharables in it. It lasts for months before a recharge with 2500-2800mAh batts. And yes, most mice differ in their DPI and tracking speeds.
IDK if your mouse has it's own software or not, but ya can go to Start Menu >> Settings >> Control Panel >> Mouse >> Pointer Options to adjust the speed. There's usually Acceleration & Speed.
I usually have acceleration set to low and speed set to medium on this mouse. Older mice had lower DPI/Tracking and needed higher speeds for me.
Hope thats useful.