Importing images

Hey guys.

I’m pretty new to flash, I’ve only ever really played about with Motion tweening and such like.

Anyway I have a query about importing images (generally .jpg) into Flash. I notice they often lose their quality, and when I preview the movie they are not always positioned in the correct place?

I understand Flash prefers Vector, and this could be why - is there something I’m doing wrong, a way to avoid it, or is it normal?

Thanks!