legacy/supremacy/etc file tags

I am a complete novice and download games for my sons to play on NDS Lites. I downloaded a file which had Supremacy in it and it wouldn't work. Legacy files seem okay, but I don't understand what these are. Can anyone enlighten me and does it make a difference? (I have used files which usually have (NDS) in them so that I know they are okay. ???

those tags are the name of the release group that dumped them. They don't mean anything in terms of file content/quality.