driveshaft problem

89 manual 535 200k+ miles
I havent owned this car long.. was driving home a week ago and i heard 2 pops and then it started grinding and lost all power. immediately took it out of gear and pulled over. earlier in the day i heard a few similar pops and lost power for a second.

i have crawled under it since then. my bentley manual shows the driveshaft consisting of flexdisc at front, ujoint at the center bearing and another ujoint at the differential. from reading earlier postings, sounds like it actually is supposed to have a cv joint at the diff. well.. mine looks, or mostly feels like a cv joint minus the boot. havent taken the driveshaft off yet. is this what my prob is?
can i fix it by repacing just the driveshaft? or have i wrecked something in the diff?

another thing.. with the rear wheels in the air i put the car in first gear and only the right wheel turned.

Not sure about the CV joint, but that sounds about right. The only one wheel turning is normal (unless you have a limited slip differential). Not having a boot on the CV joint is definetally not a good thing. I'd start looking for a new driveshaft.