For the ejector rod, just open the cylinder and hold it while you try to turn the rod. It should not turn in either direction. If it is loose, as said, it is a left hand thread so you turn it CCW (looking at it from the front) to tighten it. You can use a pair of pliers on the knurled end but put something (old piece of leather, etc.) around it so you don't mar it.
While it is open, push the ejector rod and hold it down (extractor fully extended) and take a small brush or some compressed air and clean out around the cylinder and the extractor star.
Again while it is open, grab the cylinder and see if it moves any front to back. There should be very little play. Next, with the cylinder open, take a small punch or screwdriver and go to where the cylinder pin (center of the extractor) mates with the frame and push in on the part you see. It should push in easily and you should see the cylinder release move at the same time.
If you see/feel anything out of the ordinary, that is a place to start.
After all that, close the cylinder and cock the hammer just until the cylinder unlocks and you can spin it. Hold it so you can see the barrel/cylinder gap and rotate the cylinder to see if the cylinder contacts the barrel. If it does, then you might need to put some shims in it to increase the b/c gap.
If you can't cock the hammer, you might need to take the gun apart to see what might be going on. The are very easy to take apart and if you have the manual it will explain how to do it. If you don't have the manual, you can get/download it from the Ruger web site.
