I am looking at getting some 18 rims for my 99 blazer. I am wondering what size tires i should get so they fill the wheel well and don't look weird. Its at the stock ride height as well.

I also would like to know if there is a huge difference between car rims and truck rims. Or if there really is a difference at all.

These are the rims i am looking at by the way

local://upfiles/1514/59759D93A9BF4C37AA9D4235E0C4004E.jpg

Not sure if theres a difference but maybe ask a local place? I know certain ones are FWD or RWD only...

The difference between FWD & RWD given the same bolt pattern is generally in the back spacing (where the hub mounts as measured from the inner edge of the rim). The design of the rest of the rim is basically the same.