What I meant is that you can do more at once with 64 bit. Not just having more than one window open, that was only an example. Like having a couple of windows open, burning an .iso image, streaming a video, folding, & running a VM, all at once. Depending upon your CPU/RAM, all of these things can be done together, and more.
One can only stretch 3.25GB RAM (the 32 bit "limit") so far, and this is an example where the machine would crash, if pushed this hard. Way back, sometime after 7 was released, Nibs explained this in one of the never ending "32 vs 64 bit" threads that was posted on this very forum, comparing the experience between driving on a 4 lane superhighway, vs a 2 lane road. Ian even wrote an article on it. Note that he also mentions the RAM usage between the two.
Windows 7: 64 bit vs 32 bit?
Another article on the subject.
http://zone.ni.com/devzone/cda/tut/p/id/5709
As a final note, my personal experience with running VM's has been even more positive, being that I have extra RAM to lend to them (2.5GB each), and they perform more like a "real install", even XP Pro 64 bit. I can run these, w/o a negative impact on folding.
It's a fact, if one just does a little searching, it'll be seen that 64 bit can do quite a bit more than a 32 bit can, even with only 4GB RAM. Install each version on the same machine, perform self tests, and one can see the difference their self.
Cat