FLAC (not FLAK) is kind of like a zip file. It compresses the contents, losslessly. The bitrate you see displayed is the compressed bit rate. This number will vary depending on the complexity of the audio. But don't worry. The FLACs still have all of the audio data retained. Nothing is thrown away like it would be with MP3 or AAC.
But don't adjust the compression level. Leave it at the default. You'll only potentially cause problems.
So just rip to FLAC with the defaults and you'll be fine.
Brian.