Hi Kelso,
If you have access to Datawarehouse you could extract "Visitor ID" and "total seconds spent" for the required period. Then you can add the segments (1 minute, 2 minutes, etc..) that you are looking for and group the visitors by your segment. You could do this in Excel for example.
It might get problematic if you have a lot of unique visitors (+/- 1 million) because of the file size. But I don't see an option with the other tools, maybe others do.
Martijn