Hi, I kind of had the same situation and I found some color coordinated textiles did wonders. My floor was hardwood so I added some small rugs under the sofa, coffee table and the dining table. Hope this helps.

I find that paint is also a great unifier. For instance, you could paint the legs of your table and chairs to make them interesting and more up to date. I'm guessing you like purple? You could add purple cushions to your chairs and purple throw pillows on your sofa.

No, I want to paint it a different color, maybe a washed out teal color. The couches and TV have to stay. The table will be replaced as soon as we have the money, the chairs are all wearing out after 50 years. The curtains could be replaced too.

We do have area rugs downstairs that we could use. Would an oriental rug look right on regular carpet?

I'd imagine so, they will be contrasting enough so they won't appear "layered". I think it would also help you to create a focal point for the room.