HELP!1st time buyer I need a MAC for video Editing

[m3gau]

I have never bought a mac before and don't know anything about them but i want one for video editing as i am going to get a copy of final cut studio. I am running on a bit of a budget so i was wondering if people could give me advice on whats the cheapest mac i could get that would run the new final cut studio. Would a Power Mac work or not?
Do you need special hardware for a mac. I currently have a windows PC is there any chance i could uninstall windows and just install the latest mac software.
How easy is it to run two screens on a mac?
And lastly i think for now how easy is it to upgrade the hardware in a Mac.

Thanks alot