It happened for the first time after filling tank with regular unleaded fuel.

Catalytic converter and ERG? Or, bad fuel?

Car has 142,000 well maintained.

The Subaru dealer mechanic said both headgaskets leaking, inner axle boot cracked, and timing belt must be replaced, cost of $2000. If I fix these, how much longer before I face other major problems/major costs? Should I keep repairing, or bail out now?

I have an exhaust leak at the wye connection immediately before the mufflers. 1) why do I need two mufflers, and 2) can I replace the left muffler with a longer inlet pipe that replaces the wye connection?

After I release breaks - car practically don't move until I press gas pedal. I think it's car Computer. How to reset it. Or, just wait a couple of more days, and it will reset itself ? Thanks.