I have a 2002 Olds Aurora and the A/c fan just started making noise. A friend said that something probably fell behind the glove box and is obstructing the fan and that I should be able to fully open the glove box to get behind the dash. I can't figure out how to open the glove box beyond the standard opening. Does anyone know how to release it to open more fully?

It is very likely that something is blocking your fan.
The glove box is fairly securely attached. You may find it easier to remove the blower motor to remove any debris that may have gotten into the fan.
Remove the lower passenger side panel, under the dash.
Disconnect the connector and remove the screws that hold the fan.
Reinstall in the opposite order and check your work.