Hello John -
If your tractor stopped moving forward and the mower kept running, you have the 2 stage clutch.
There is a fairly simple adjustment that usually cures it. Described several times here, and on Big Dean's website - I don't have the link, but it's cited here several times a month.
The oil leak repair will need a split. Not a difficult job, but some critical points involved - there's a writeup in the archives on it.
Good luck! The 35's are great tractors. I used to have the blue ones, back when they were grey...