Mykey - I haven't been happy with rendering to AVI but I love how it turns out when you render as a Quicktime movie - not still frames, but the actual movie - using the Sorenson3 codec and setting the quality to either next to best, or best (of the Sorenson codec - while keeping the Vue render quality to just Broadcast, believe it or not). You can drop this file directly into Vegas for editing or compositing.

I'm wondering if you ticked Depth of Field and didn't realize it (just throwing out ideas - hard to tell what you're asking without seeing it), and now it's "blurry"? Could you post a still frame of the middle of the animiation you're unhappy with (play the animation, pause in the middle and do a screen grab)?