A) I never recommend changing to anything new when trying to pinpoint a problem. Why add something to the equation. I can't really see how the EGR system would be causing your stalling. I mean even if the valve was stuck open all the time, it normally is open at idle anyway (I believe...it should only close at full throttle), so that wouldn't make a difference. So unless you have some huge plenum leak in hte EGR pipe or something (which would be easy to find via pressure test)
Something like this:
...I don't see it being the problem. Speaking of which, have you pressure tested???
B) Are you sure that is the only code your ECU is showing? Perhaps scanning the codes will lead you to your problem.
C) EGR plates should throw a CEL on OBDII cars, and I believe hybrid ecus as well, so basically you are only good on 91-93s, without putting in some type of resistor to fool the ECU. Now I say SHOULD, because for some reason, some people have gotten away without ever getting an EGR code, however, typically you should expect one to come on. Even then, you will most likely fail any type of visual emissions inspection...and probably fail an exhaust sniffer.
D) You can just install the plates, or you can delete teh entire system...it's up to you. But again, if you don't have a 91-93, you may get additional CELs if you remove the EGR solenoid.
E) not really sure how much gas mileage suffers. It would only affect your gas mileage at partial throttle and low load, allowing more clean air into the combustion chambers, so your gas mileage may suffer a tad under those conditions...but again, I don't know how much.
F) if you insist on doing this, don't spend $50 for plates. Just cut some aluminum or something in the shape of the EGR gaskets, but without the hole in the middle and just use that. Save yourself $49.