I had purchased windows 7 professional from Microsoft. There are 2 things i need to know.

1. Can i use my 32-bit license key for a 64 bit installation?

2. I need to download 64 bit. After bit of searching i have found


I need to know if this is authentic place to download since ill be using this copy on my laptop and i dont want to download a warez or other changed copy of windows.