well the best person to answer that question is the lady who is doing the afterv fx work for you. only she knows what her system can handle. I would recommend first and foremost uncompressed avi if she is on windows or uncompressed .mov if she is on a mac. otherwise if she cannot handle uncompressed because the file is too big you could give her a quicktime animation. i think the file is a little smaller than uncompressed but i could be wrong. but qt animation is still a big file. you could also render out the video as an image sequence I recommend a TIFF sequence suing LZW compression to keep the file sizes down. give her the image sequence she can add the fx and then she can render out the final product as an image sequence again which you can match up with the audio track on your pc. she can also give you an uncompressed file which you can then render out to cineform.