Talking about misconceptions...

Quote -
Despite this limitation, 4 GB on a Vista 32 machine is decidedly NOT a scam. No single program would normally get 2 GB, but you can run more than one at once! If you have 3 such programs, you need 6 GB of RAM, even if none of these programs itself is a 64-bit app.

They don't use RAM (as in random access memory) but virtual memory (combination of RAM, swap file,...) That's why you can run a bunch of programs  which need more than the RAM available in the PC at the same time, because there's enough virtual memory via the swap file available.

Quote - Without 4 GB, you could not render a 2 GB scene and keep working on other things, without doing a crapload of swapping.

Her OS is only using 3 GB, as shown under physical memory. That's because the hardware (like the graphics card) is using part of the same adress space as the RAM and there's no remapping done.

Well, it's getting more and more complicated, I guess... But the important things have been said :-)