FLAC or Windows Lossless for music archive?

There is no audible difference between Windows Lossless and FLAC. None. Zip. Zilch. Anyone claiming to hear a difference is making things up.

This is absolutely correct -- these codecs are indeed lossless. It may be possible that there are some products or software out there that screw up the decoding/playback processes to different degrees . . . but there is absolutely NO sonic degradation associated with these file types. They also both support high-resolution sampling rates and bit depths.

But they do behave very differently in terms of the metadata, FLACs are supposed to use Vorbis tags, and WMA lossless files use a propritetary tagging scheme . . . both of these are different from the ID3 tags used for MP3s. This may affect how easily you can take the files between various playback platforms and still keep them organized in the way you like.

So I would recommend that you decide based on what is best supported by the software and hardware that you wish to use for organisation and playback. And since they are lossless, you can transcode between formats with no loss in sound quality, if you ever need to.

Use FLAC, since it's supported by squeezebox on the hardware level, this allows you to seek forward/backward and jump to any point on a track. Where as Windows Lossless is only support in software and cannot perform such function.

Can someone update me or give me a few links? I'm familiar with the squeezebox, but never looked deeply into it due to misconceptions, no dire need to upgrade, among other things.
This thread (thanks all!) resparked an interest. I assume a squeezebox be run from a external hard drive (usb2.0? SATA?) to a DAC (how much does the DAC, good quality DAC help?). Any recommendations or pointing me where to go would be great!

I have a terrible tendency of scratching / loaning forgetful friends my CDs and this would be great!

The Squeezebox web site is http://www.slimdevices.com and they have an excellent users forum plus a wiki. Between those you can learn just about everything you'd need to know about the Squeezebox.

That said, a Squeezebox won't run directly from an external drive. It needs a computer of some type to run the server software. They have free versions for Windows, Mac and Linux that you can download and experiment with before you buy one of their devices.

I run a SB3 (now called the "Classic" Squeezebox). I use a dedicated Linux server to house the music (over 39,000 tunes). The SB3 feeds an external DAC (Lavry DA-10) which goes to the power amp/speakers.

It is an excellent way to fully access and enjoy a large music collection.

A final note. If you decide to run a music server system, make sure you keep backups of your music. Re-ripping thousands of CDs is not a project most would enjoy. I actually keep two backup drives with one of them off premises.