Welcome to the Forum - Antialiasing only affects the 3D view window, the way I use it is to antialias the 3D view (3D window menu - 3D - antialias) the select Edit - Copy 3D view to the clipboard. From there you can paste it into your graphics app. Don't forget to turn off antialiasing because it wil slow AC3D waaaaaaaaaaaaaay down.
.The only way to improve your renderings is the settings in your render program. Woody has a couple of good overviews in the tutorial section.
Have Fun
Art