How convert raster to vector in Illustrator

but i think it take too much time to make many  different type of background.

what do you recommend i'm want make a 4 min animation clip so what can i use in the background

raster image or self made illustration background

would you please send me tutorial about creating  background.if you not have any tutorial please give me some tips.

This can help How to work with Live Trace | Illustrator CS5 and earlier to understand this feature.

There is no "conversion," per se. There is an automated "trace" feature that could, but often won't, satisfactorily interpret the raster image's color breaks and approximate a vector-based equivalent. In most cases, it would be better to trace manually and assemble a vector composition of sound construct. That is, if a vector equivalent is truly required for some process or other, but that's rarely the case. Is there some reason a raster image can't be used as a background in your animation?

Technically yes, but in many situations this would not be a better idea than simply using the non-vector image.