What wheel is this and how big of a tire can I run?

How wide do you want to go? I ran 15x7" cop rims on my Duster for awhile, they had a 4.25" backspace and I was able to run a 225/60/15 but that was pretty well maxed out for clearance. You can't run a whole lot more than 4.5" of backspace in the front with a 15" rim because of UCA, ball joint and brake clearances, and because of the limited sizes/profiles available tire height becomes a problem as you go wider.