As Jay said, the starter screech usually means lack of lubrication of the small plain bearing inside the starter. However servicing this needs to be done carefully: just one drop of oil on the plain bearing, absolutely no oil anywhere else, and keep it all very clean. There are specific instructions in the B&S manual: Starter Clutch Inspect and clean starter clutch assembly as necessary. Do not oil ball cavity area. Place one drop of engine oil on end of crankshaft before replacing clutch assembly on crankshaft. Tighten clutch to torque noted on specification sheet for your model engine. DO NOT run engine without screen screws assembled to clutch. NOTE: Clean ratchet by wiping with cloth only.
With regard to the governor, usually the first thing to look for is a bent governor base (the punched tin piece that is the base of the governor). If you post a picture of this part, including the springs, we can discuss it specifically.
