The answers depend on how you are outputting your sound and what OS you are running and what hardware you've got...
MC can rip the DTS cds without any problem, and using a lossless compression (like APE or FLAC) will preserve the bitstream.
If you are connecting your computer to an A/V receiver or DAC that is an external DTS decoder, then your signal path needs to be 'bit-perfect', and how you achieve that varies depending on your hardware and OS. The simplest way is to be using a sound card (or chip) that has ASIO drivers available.
If you are connecting your computer to multiple speakers with analog connections, then your computer needs to do the decoding. I'm less certain about this, but I believe there are DirectShow filters available to do this decoding. I believe recent versions of ffdshow and AC3Filter can accomplish this. The simplest way to install ffdshow without a lot of extra gunk is to find the CCCP codec pack--follow the instructions on installing it--and enable DTS decoding.
The DirectShow configuration page of the wiki will be of great help to you there. Check out
http://wiki.jrmediacenter.com/index.php/DirectShow_Playback_GuideHope this helps,
brad