If the catalytic convertor were locked up usually it would be evident when out on the highway. A lack of power, especially in acceleration will be noticeable as well as maybe sounds of pinging in the engine due to high combustion pressures. The best way to check the converter is with a pressure gauge put in the socket of the oxygent sensor and running the engine. The pressure will build up.
Sometimes you can tell if the converter is bad by knocking it as mentioned. Just don't do it with a hammer or it will be bad. Make sure that the rattling that you may hear is not heat shields.
On the matter of your engine running, I had the exact same problem and no codes that could tell me anything other than 58. I finally came to the point that it had to be the MAF sensor and just changed it and it was fine. If you disconnect the MAF sensor, it should run in the "Limp" mode. This mode just substitutes values in by referencing other sensors such as rpm and throttle position and comparing them to a table and then assigning a MAF value that will work (just not the best).
Now, you were saying that it would die after about ten minutes. Same problem I ran into last year when the crank sensor started going on my car. When the sensor heated up enough the output value drop down below the threshold for the zenor diodes in the control module to actuate. The car would then stall. Letting the car sit for 15-20 minutes would allow it to start again like there was nothing wrong.
Check your plugs as well. The back 2 closest to the alternator are a continuing problem with mine. They get carbon tracking on them and creates a miss (usually under load). How does the fuel filter look? If you have any question as to it just change it. It may be supplying enough fuel to the engine at idle but under heavy acceleration it may not be able to get it there quick enough and pressure may briefly drop.
Anyway, hope this is some help.
1992 Bonneville SSEi
White, grey Leather interior.
Tinted windows and blackouts on headlights.
Custom high flow exhaust, Everything replaceable - DONE
300 000 kms original engine, tranny 2 rebuilds.
Playboy Bunnies Embossed in Tint. Oh Yah!
Ever Seen a Polar Bear in a Snow Storm?