I guess you mean "3rd-generation tracker", and Buzz happened to be the first of them - so yes, it clearly is one, and there were quite a lot of sceners using it, probably even these days. No idea about Skale, apart from that it's no longer developed.
About the compos, the easiest would be to just go to a demoparty and read the slides carefully. Not everyone reveals the tools they use, though.