I use ABR 128 for a 1cd rip. If the movie is already approaching 2 hours you can do ABR 112 if you want. For a 2cd if the ac3 is 192kbps then you can just keep that one, else APS Standard is good. Some people may not agree with what else I do...I downmix from 48kHz to 44.1kHz because SSRC is good at that and it sounds the same to me.