What kind of tires should I buy for a 2002 Chevy Tracker?

Tracker what..

2WD - 195/75-15
4WD - 205/75-15
ZR2 - 215/75-15

Those are the OEM sizes... as far as make? Well.. depends.
Where do you live? DO you get snow? Lots? A little? Rain? A lot?
How much do you want to spend?

Need more info...

Take a look at the Tire Rack Tire Rack - Your performance experts for tires and wheels (http://www.tirerack.com/index_w.jsp)
Select your care from the dropdowns, pick tires, then select "Decision Guide"
It will help you pick