Re: 32bit or 64bit
Calling it "AMD64" does confuse newbies, as does the "32-bit (recommended)" on the Ubuntu website.
What's wrong with "If your computer has a 64-bit CPU, use this image" and "If your computer has a 32-bit CPU, or you don't know your CPU model, use this image". And then name the 64-bit image "x86-64".
I try to treat the cause, not the symptom. I avoid the terminal in instructions, unless it's easier or necessary. My instructions will work within the Ubuntu system, instead of breaking or subverting it. Those are the three guarantees to the helpee.