If youve set the track numbers in the meta data correctly, sorting by album will sort the tracks correctly within the album. And no, if its not sorted right now, it wont be sorted right once you burn it. It will retain the order its displayed in iTunes.
My iTunes library is pretty organized (11000 songs), and when i drag songs into a new playlist to burn to a cd, it will burn in the order I drag the songs into the PL.
It should. To add to Mal's response, if you don't know how to edit the meta data: right click/control+click/two-finger tap [] select "Get Info" and you should see a place to add a track number. "Track _ of __"