Sansa dispalys "Unknown Artist/Album"

I don’t think it’s the settings of the Fuze (there are no settings that influence ID3 tags) but rather the version of the ID3 tags you used.

With the latest firmware, the Fuze supports the ID3v2.4 specification so I suggest trying that. Unfortunately you don’t mention what types of tagging you tried so it is hard to guess if it is anything unsupported.