Longest length movie that will fit onto 1 disc?
 

If extras are removed, what length will fit onto 1 DVDR?
i.e. like a 120 minute movie....130 minute...etc???

It depends how big is the DVD-R and what type of video file do you want to put on a DVD!

On a standard 4,7 GB DVD-R you can put (to have a good quality) approximately 100 minutes of film if Audio is in PCM format and about 125 minutes if audio is MP2 format (MPEG-2 file)

If you want a worse quality you can stored on a 4,7 GB DVD-R also 270 minutes of film (if audio is in MP2 format) (MPEG-1 FILE)