Guardian,
TCF is not a compression format, but rather it is a release group; otherwise known as The Chosen Few.
There is no difference between DivX and XviD, however there is a shift towards the XviD format, over the 'older' DivX compression format. As far as viewing and playback is concerned, there is not much difference between the two video codecs.
Do these formats support "3D audio"? It depends on what you mean. Most of the time, they will be encoded using AC3 5.1 channel audio format (using the AC3 audio codec).
Typical settings, for XviD files are:
AR's of 2.35:1
Resolution: 640x272
Video bitrates: ~1155kbps (over a thousand kbps)
Audio bitrates: 448kbps, 48kHz, VBR MPEG-3 (MP3)
SVCDs will generally have much higher video bitrates, spanning more than one disc; oftentimes two or more (compared to XviDs which, usually, fit on one 80-minute disc).
Typical settings, for SVCDs are:
Video bitrate: ~1800kbps, up to 2450kbps, 4-pass VBR
Audio bitrate: 224kbps, 44.1kHz
Resolution: 480x480
Hope that helps you,