The 151Rum method should have turned off the service light. It is strictly dependant on the odometer, the number of miles driven. No other inputs, so having dirty oil makes no difference.
When an O2 sensor goes out, you will get a check engine light. No need to replace them. Unless, of course, your gas milage is terrible and there is no other elplanation for it, like porus vacuum lines and elbows or PCV system dirty.
You should have gotten a code when the engine stalled, UNLESS it is gas supply related. Like fuel filter, ran out of gas, fuel pressure regulator problems, fuel relay, etc.

Klaus
--
(V♂LV♂s 1995 854T, 1998 V70R)