Is the jump from 32 to 64 even noticeable?
If you were running software limited by the 32 bit address space (i.e. 4GB of RAM) then it's unlikely you will. 64 bit processors do run a bit faster when they're in native 64 bit mode and not 32 bit but unless you're doing intensive calculation work, it's unlikely you'll notice. There's certainly not going to be a sudden magic speed increase.
Nothing to do with graphics resolutions I'm afraid, they'll stay the same!