WAV files and Apple Lossless

I have spent weeks ripping about 700 CDs into iTunes using WAV files, because I thought they were the highest quality, only to figure out that Apple Lossless will provide the same audio quality but utilizing much less space on the external hard drive. How do I convert those WAV files to Apple Lossless? I have another 700 CDs to rip, but I want to get this done before I continue, so everything will be in the same format. Am I right to use Apple Lossless, which I understand is a FLAC-type file, rather than WAV?