There is no exact answer to this question. Results vary depending on hardware (which you didn't tell us much about), usage, installed software, and other things. There's no way to know for sure, but I can give you a generalization.
Cinnamon is probably the slowest DE you can use because it uses plenty of visual effects and developing technology. I would expect MATE to be slightly faster than Cinnamon because it is more "boring". I would expect XFCE and LXDE to be faster than either of them because they are simpler and often used by distros that are optimized for speed and low overhead. I think KDE is also faster (though I haven't used the most recent version). There are also less well-known environments (a phrase I'm probably over-using) that can run faster at the cost of less support and fewer features.
You can improve the performance of most desktop environments by removing or disabling crufty programs that normally run in the background. For example, screensavers are obsolete, so you can safely disable your screensaver daemon. Using Synaptic or other package managers, you can find and remove programs that might be slowing you down (but don't do this unless you know what you're doing or you're willing to reinstall a broken OS).
My computer's specs are a little below the ones you gave, and I suspect it's a few years older. It currently runs Mint 14 with an optimized MATE environment. I rarely notice any lag (though I don't know if I did before optimizing it).
The only way to know what will work for you is for you to try something yourself, but you should be fine with almost anything that isn't in the Cinnamon/GNOME3/Unity group of crufty eye-candy environments.