I would buy nothing less than Windows 7 64-bit Pro.
32-bit only addresses 3.5 GB RAM ... 2012 Macminis can hold 16 GB.
64-bit Home addresses 16 GB RAM.
64-bit Pro addresses 192 GB RAM and han an XP mode.
This is all about having a good version of Windows for future use. Yu can buy "Syem Builder" version of 64-bit Pro for $140.