to the right of your Fkeys is a key called 'Prt Scr' (probably, depending on your keyboard). press that.
now open up photoshop or paint or what have you and paste. presto, one screenshot.
as for the other question, i think that's maybe a case of creating an addon. someone else needs to step in on that one, as i have no experience in that area. unless of course you mean a
real building or billboard, in which case you'd have to contact your local printers...
cheers