If you don't do any gaming, go with something that's just comfortable as resolution and such won't be a big factor for you. Although most gaming mice are very comfortable, and are nice to have for a lot of things other then gaming, the prices are also way up there.
I bought a new mouse as a prelude to my new computer that I ordered the parts for last week, and so far it's proven to be a great investment. You have no idea how nice a quick, responsive, comfortable, adjustable mouse is to have until you use one for a while and get used to it.