I am, firstly, an idiot. Just keep this in mind while I do my darndest to explain my problem. Well, this problem, anyway.
I have a NVIDIA GeForce 6150SE graphics card. The desktop animations for Cinnamon, Gnome Shell, and Unity are what I can only call "sticky"- they're slow, and they freeze for a half a second or longer. Opening a menu on Cinnamon takes a long time; same with Unity and Gnome Shell. This is with the Nvidia driver, now.
When I use the open source driver, the animations are smooth, there is no lag for the menu. But, because it's the open source driver, it's noticeably duller-looking than the proprietary. Things like Minecraft are terribly slow using Nouveau.
Also, I dual boot with Windows 8, and its flipping squares and twirling tiles and such. So, as win* works fine, and the open source driver on Linux works okay (smooth animation wise), I can only conclude it's the Linux NVIDIA driver.
Investigating this, I was led to understand (which is often code for "I misread something on a random website months ago") that the reason for this is that Nvidia does not really support a card as old as mine for use with Linux. It does for Windows, but not Linux. For this reason, I've been choosing between MATE, XFCE, and so forth, which work fine with a Nvidia driver.
This has, incidentally, been going on since Mint 12's version of Shell and Cinnamon.
I genuinely like MATE- it's solid, and I enjoy making it look like old-school Ubuntu Hardy Heron, just because. But I'd prefer to use the newer desktops, if I can get them to work with my driver with a minimum amount of hitting my OS with a wrench.
On another thread, a suggestion was made to install a legacy NVIDIA driver, which is... heaps and heaps of fun, if I remember from the last time I had to manually install one of those things. Is that correct? Is there a solution to this problem, other than, "Buy a new computer, cheapskate"?
Thank you for your indulgence.