Well I'll start off by reminding you that WoW uses a very old engine which doesn't put much strain on any computers at all, unless you crank the setting all up to maximum.
Rift on the other hand is much more demanding. I hate to say it, but even when your GPU was launched, it was a budget card. It's little wonder that it struggles with Rift at the best of times, as Rift is oddly demanding of systems considering that it's an MMO (meant to appeal to the mass market). Also, your RAM is a little low. Ideally, to get maximum performance out of games you need 4GB. You can benefit from up to 8GB (if you have a 64-bit OS), but past that it becomes somewhat redundant. It's good to see that you've got a Quad Core CPU, but it's running a little slow by modern standards (2.4GHz). If you have a proper CPU cooler (NOT STOCK!) then I'd overclock a little bit just to eek out some added juice.
However, all of this doesn't account for the fact that it's running at 2FPS on ALL settings. It should correlate negatively.
Therefore, check that your drivers are all up to date.
Run registry cleaners, defrag and virus scan.
Check for processes that are hogging your memory (ctr+alt+del<Processes.) If you don't recognise them, or if they look shifty, end them.
Tell me what cooling solutions you use?
And how much wattage your PSU provides? (make and model please)
Do you notice any other issues with your PC? Are your problems just during Rift, or have you noticed other things (slowing down generally, problems with other games, crashes, BSOD, etc)?
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It could be that your GPU is struggling with Rift and generating a lot of heat, which is damaging it and negatively affecting performance.
But these are just random guesses, so until you answer the questions I posed and follow the preliminary steps I advised it's hard to say (for me at least - maybe someone like Hexit can help you better.)
Good luck!
-Nih