Best muxing software for editing ripped tracks?


Two questions, really:

What’s a muxing tool that has a low incidence of problems and/or is easy to use? I have to edit some footage ripped from DVD, which I ran through DVD2AVI and TMPGEnc as demuxer (ripping out AC3 files as sound…I have heard TMPGEnc is NOT good for making sound files, creating lags…should I be worried? If so what program should I use to pull the audio out?). To edit the audio and video as one, I need to mux the files to an MPEG and then demux again to get ready to burn to DVD, etc., etc…is TMPGEnc a good tool to use for that muxing process or should I be looking elsewhere?