I am planning to buy Vista but I am confused with some talks on internet. It looks like that different version of Vista will not support 64 bit processors and Dual Core processors. There are different theories, but it seems that people think only more expensive versions (like Vista Ultimate) will have support for 64bit processors. Is this a true?
No, it is not. It just one more myth and nothing else. Vista has a support for 64 bit processors and Dual Core processors in every version, so you do not need to worry about this. If this was the only thing that prevented you from upgrading to Vista then you can safely purchase and install your copy of new Microsoft operating system.