Code 55 is the end of the self test. Not a worry. The fuel pressure can be checked simply by installing a gauge in the high pressure line. 45 PSI +/- 3 PSI.(V6) 2.5 I 4 is 14 to 16 PSI, You will need a T fitting to install the gauge in the pressure line, run the vehicle until it stalls and check the pressure. Also, see if there is spark when pressure is lost. The ASD circuit will not allow fuel if there is no fire. No fire will require further diag. Given the year of this unit, wiring corrosion at the pump or the relay may be an issue. The pump could be suspect as well. Be sure to check for spark before installing a pump..
The power windows are not controlled by the body computer in these vehicles, so it is a standard power window. Most likely not related to the stall issue. The window can be tested a few ways, best is to remove the door panel, re install the switch, probe the 2 wire at the motor to see if power and ground are present. In the up position, power should be on the LT Blue wire and ground on the White wire, down, power will be on the White, ground on the Lt Blue as you are reversing polarity with the switch. The wiring diagram can be found on Google..