Fine art quality from a digital file means one of two processes. The first is inkjet on acid-free paper. The second is a laser exposure system such as a LightJet, Lambda, or Chromira, which takes a digital image and exposes it onto traditional photo paper. I personally prefer the latter but others like inkjet. Either can be done at a professional lab/print shop. Enlargements generally require extra sharpening.
Standard printing specs:
-TIFF is default but they'll also print JPG and a few other formats.
-300 dpi (305 dpi for LightJet) @ canvas size.
-Lab will specify either sRGB or Adobe RGB 1998.
As for mounting, it can be done onto acid-free archival matte, but this is expensive. The preferred and generally cheaper option for a lot of people is skipping the traditional matting process altogether and opting to have the image held into the frame w/ a layer of matting spacers.