After Effect New Composition Select Preset "DV/D1 PAL".
no need to touch any settings, this will be beter if u later wanted to export to a DV tape. (Or "DV/D1 NTSC" if ur DV Camcorder is NTSC)
Export to streaming video is another part.
just use the AE's wmv compressor any choose the setting
whatever u like step by step.
Or u may be render the movie made in AE as AVI or MOV or images seq and use other program's compressor to do the compression.