YOU CANNOT UPGRADE TO A 64-BIT OPERATING SYSTEM! It is literally not possible. A 32-Bit computer can only use a 32-Bit OS and a 64-Bit system only a 64-Bit OS. Unless of course you want to buy a new computer.
You can put a 64 bit OS on the same computer as you had a 32 bit. In fact you can put the 64 bit on the same hard drive as the 32 bit was on. Simply save what files you need onto an external disk or secondary hard drive, format the boot drive (where the OS is) then install the new OS onto it. You can then move any files you saved elsewhere onto it and set up any settings you need to.
Next, 2 GB of RAM is good enough for PR. If you have extra cash, then you can buy more (max of 4GB total).
You can get by with 2 gigs but you're cutting it pretty close, especially if you've had them for a long time and they have lost modules (which means less actually memory space.) I'd have to say, like Johncro said earlier, get at least 4GB of memory for your system. If you do plan to go down that road and add memory, I would suggest you but a whole new set to ensure compatibility and reduce the amount of dead modules.
However, VRAM is more important to PR and I see that your 1GB is more than enough.
Video memory has the least importance of any hardware in PR. System memory is far more important. There are cards with half a gig on them that will run PR very well. On one of my computers I run PR with an integrated card which means that it does not have any memory of it's own, it shares the system memory, which I have 6GB of. IIrc, VRAM has the most effect at larger screen resolutions like 1920x1080 and higher. Still, with the cards coming out these days and the screens too, it's probably best to get a card with at least 1GB of memory (which for newer cards I don't think you can get less.)
I believe that the OP's problem is caused by overheating, corrupt software (drivers or BF2/PR), or damaged hardware.
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