Music Rescue supports all iPods on the market in October 2008, which includes:
If you have an iPod model not listed here - just try it! If Music Rescue doesn't support an iPod, it'll just fail to load it, and won't damage any data on the device.
If you're unsure which iPod you have, see the Apple Knowledgebase article: "Identifying iPod Models".
An up-to-date compatibility list is kept on our support site - see the article: "iPod Compatibility Table".