Verified answer

Transmission issue should not be related, however it is POSSIBLE that the shifter linkage is not setup properly. It is all mechanical that year, if it won't go into reverse either the transmission is shot, or the linkage isn't adjusted properly.

Fix the speedometer issue. When you dig into it, you may find the issue with the other gauges. First step is, does your check engine light work properly? If yes, are there any codes?

If no...need to find out of the VSS is working properly, best way is to find a "scanner" (not code reader) to see if the ECM is seeing a vehicle speed when you are driving. VSS is critical to proper engine operation (regardless whether it "feels" right or not) so speedometer not working could be critical, or it could just be a convenience thing for you...redneck test, which is not authoritative, is if your cruise control works. If it does not work, it COULD be a VSS issue, but of course cruise could have failed too.

The dying at a stop/drive issue could be vacuum leak, or a VSS issue. Again...figure out why the speedometer isn't working, and if related to VSS, fix that.