Perhaps, you could offer the following?

why you want a 64 bit OS (as opposed to 32 bit)

what you propose to do with it that requires 64 bit over 32?

You can invite more trouble than it's worth with some distros on 64-bit.
If you're just starting out with linux, installing a 32 bit Os may end up being the safest and easist way to get started.

I've found that ubuntu 64-bit runs no better than the 32 bit version on my 64-bit hardware but certainly provided some headaches wrt drivers.

Regards