More details on my question
I think you should just get Windows 7 x64 for future proof. You don't want an old OS that wont be supported in the coming months. Windows 7 is the now and the future and you'll just be holding yourself back and seriously waste money on a old product. 2GB of ram should be able to run on a x64 bit system. I had 2GB of ram on a Windows 7 x64 before I upgraded to 6GB of ram. It wasn't absolutely 'smooth' but it will work just fine until you get your 4GB of ram.
First of all, thanks to all of you. If I had known of this forum before I would have more hair on my head today.
I didn't think to provide more details before. Rectifying that problem now.
I have an Athlon 2.01GHz sitting on a ASUS A8N SLI with 2GB RAM and a 128MB NVidia 7800 video card with a Windows 7 recommended resolution of 1650 x 1050 (or something like that) on a 20inch Flat Panel Monitor. I am running Windows 7 32-bit on it right now. I am not sure when I'll go to 4GB RAM; I want to but it could be 3-4 months till I wrangle up the money. I am already in possession of both 32-bit and 64-bit Windows 7 OS so that's not an issue.
If I understand correctly, one opinion is that 64-bit Windows 7 takes up a lot of RAM right of the bat and therefore one shouldn't install it with just 2GB RAM unless the change to 4GB+ RAM is impending. That means stick with 32-bit and re-install with 64-bit only AFTER 4GB+ RAM is available in the computer.
Another opinion which I like

is I will not experience any perceptible slowness if I install 64-bit OS right away. This I'm hoping will also be the final conclusion subject to more information I'm providing below.
I guess part of the answer depends on the rest of my hardware - details on which I provided above - and part on how I'm going to use the computer. I definitely expect to use the computer for audio/video encoding / processing. Creating home videos, encoding to different formats to play on different devices etc. However, I am no Gamer. In fact I don't even expect to install any game whatsoever on this computer.
So with this information, would those recommending I do not go 64-bit Windows 7 right now, change their opinion? As an aside, does 64-bit OS make the computer heat up more or something? Sorry if this is stupid question.
Thanks much.
