Regarding Avast, you really may not need an anti-virus on Linux; many experienced Linux usere don't use an AV because there are currently no Linux viruses in the wild and haven't been for years. I'm an exception--I do run one (AVG), but I couldn't get Avast to work either.
Netflix does not support Linux; it has to do with DRM
. The others I can't speak to. You would probably learn more, more quickly, by entering "[service name] Linux]" in a search engine.
You might want to look into Myth TV
, which is a DVR-like program for Linux.
If you have media files already, Linux can stream them quite nicely. The Arch Wiki has a nice article about that
. The questions start to arise when you start to ask about commercial streaming services, where DRM becomes an issue. Because Linux is open and DRM is closed, issues arise.
Hope this helps a bit.