You would have to asking Hosting support about data hosting GB levels.

Your domain name is registered at the place where you purchased the domain name. If you buy through WA Site Domains, then it is WA. If you buy the domain name through, say, Namecheap, the domain registrar is Namecheap.

~Jude

Thanks for the Insight guys! I don't think im in the gigs dept just yet :) I will do some more research!

I read somewhere the media library is 3gb, you can ask support if this is true

This often depends more on the plan you choose with your provider/host. The domain is registered with who you bought the domain from and by other entities as well in some cases.
~Debra

Not that I know of...

Obviously having excessive plug-ins, images, videos can slow down your website's speed or loading time...

I'll follow this thread, I'd be interested to see where it goes :)