HydrogenAudio has a good comparison of lossless codecs here.

Personally, I rip music from CD to FLAC using ExactAudioCopy.

Then I use Foobar2000 to convert to lossless WMA and apply AlbumGain to normalize the volume across all my CDs.

There's probably more efficient ways to do this, but this is how I roll. I like WMA because it's the easiest lossless format to use with Windows Media Center.