I'm using an old system with E6420, 2GB RAM and 1GB GT 630 nVidia Graphics...Is the system going slowdown if I install Windows 7 Ultimate 64 bit or Windows 8 64 bit ? or Is the best solution go with Windows 7 Ultimate 32 bit OS ?
The short answer is no. Your computer should not suffer because you are running a 64bit OS. I have been running Windows 7 Pro 64bit on a old laptop for more than two years now and it's as "healthy" as it ever was.
Are 64 bit drivers available for your computer? I would suggest you check to see if the computer has support for Windows 7 64 bit if you haven't done so already. From what I have read the 64 bit OS shouldn't slow your computer down. You could always run the upgrade advisor to check for potential issues - http://windows.microsoft.com/en-US/windows/downloads/upgrade-advisor
I have already installed Windows 7 Ultimate 64 bit...The system performs fine without an issue..I played many latest games with this configuration..I think my system is over-perform well..But one of my friend said 64 bit OS is bit heavier for your system and that's not good for Its health..Is that true ?
The short answer is no. Your computer should not suffer because you are running a 64bit OS. I have been running Windows 7 Pro 64bit on a old laptop for more than two years now and it's as "healthy" as it ever was.