Requirements for quality sound

[CPeachey]

I have put my record collection on disc as FLAC files and now plan to build a media pc to play them back through my hi fi speakers.
Do I connect the sound card directly to the Hi Fi amp?. What would be a good sound card?
Does the software/operating system choice make a difference? if so what would be a good choice?
Any tips appreciated.
Chris:

[Rubberman]

I use the audio high-def hardware built into my Intel motherboard. I'm not using my hi-fi to play sound, but have a nice set of Bose computer speakers (dual inputs so I can have both my workstation and laptop connected at the same time). I use the standard ALSA sound system software that comes with Linux, and it sounds quite decent, even for stuff like classical, jazz, folk, and rock music. Normally, I rip my CD's to 192kbps mp3 files so I can also put them on my phone and play them on my car stereo (it has a usb port and can play mp3 audio files just fine). I'd use flac or ogg if my car stereo could handle them. FWIW, I find that 192kbps rips is a good compromise between size and quality.