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This is an OEM version and is 64 bit and does not include SP1.

Let's start with the easy part: get the one with SP1 for the same price.

Unless your Mac has 8 GB or more and you are planning to give the vm 4GB or more you really don't get a benefit from 64 bit. In fact it will tax your system more than 32 bit. I would generally recommend 32 bit for a vm.

Finally note that OEM/System Builder versions are intended for use on computers for resale, it will work in your vm, but the validity of that license is questionable. Since it is a vm, you won't have the other issue with OEM, that it is tied to the original hardware it is activated on.

B
 
Long version of what balamw was saying (or perhaps just explained in a different way):

Windows 7 has different licenses, OEM or System Builder is really only meant for custom built computers being sold to a customer. As such Microsoft provides no support for those Windows licenses (it's up to the builder/seller to support). Also those licenses are non-transferable to any other computer besides the one it was originally installed on.

This is the appropriate retail product; http://www.amazon.com/dp/B002DHGMK0/, it includes both 64-bit and 32-bit install DVD's. Although it does not say if SP1 is integrated.

I'd like to point out that Microsofts customer service sucks, so if you go for the OEM version the only thing your really risking is some activation problems if you ever try to move the install to a different machine (and even this can be solved by calling the activation phone number and answering some automated questions).
 
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