jagged render
 

I have followed the car tut at digitaltutors and finished it, i rendered and it looks good ,but not at all professional as my chrome wheelsa are really pixelated.how do i improve this jaggedness?my render time was 1hr 5.

first try taking the image into adobe and sharpening it in the filters.
or try uping the anti aliasing.

usually change the sampling from -2 and 0, to 0 and 1, then 1 and 2 ..