Hi there
You can render it from bryce to uncompreesed AVI - that would be lossless - however - you cant stop rendering at a given time and then pick up rendering again later. Bryce doesn't allow that.
You can chose the approach of rendering frame by frame to BMP - that would give you the possibility to pick up rendering at any given frame in the animation. I've made a 20 sec animation in 800*600 render with 255 in quality on a quad core 2,9 ghz pc doing nothing else - it took a week to render !!!!!! - Now maybe the quality setting is overkill as animation alwyas introduces some kind of bluring - so maybe one could settle with a lesser quality ..haven't experimented with that. As for the framerate most standalone players and/or PC's can play the videos with the proper framerate for the particular country - good luck with you animation and may you be patient :-)

Best Regards
Aren