Tire questions...help?

255 would be the proper fitting size tire for a 9 inch with wheel. A 245 will fit just fine but with a little stretch. Some shops may put a 235 on there for you but it will look goofy with the rim of the wheel sticking way out. 265 or even 275 will probably fit too but have a little more sidewall flex so I think 255 would be ideal.