[QUOTE=trickice;2096604]Will Microsoft Windows 7 Home Premium w/SP1 64-bit-System Builder License and Media - 1 PC take me from Vista 32 to Win 7 64?/QUOTE]
It'll allow you to install Win 7. The old OS is irrelevant; you can use the System Builder copy on a blank hard drive. As it's not permitted to perform an upgrade-in-place from 32 bit windows to 64, you may as well backup the OS drive and reformat it.
In principle, a System Builder license is supposed to be used only on a system intended for resale:
Is it OK to use OEM Windows on your own PC? Don't ask Microsoft | ZDNet
As far as I know, there is no enforcement of this. Newegg sells system builder licenses without any bundled hardware requirements.