Can i make 32bit into 64 bit on xp home ?

actually it is compatible with 32bit. from their website:
http://www.nuance.com/for-business/by-product/dragon/dr...

System Requirements

The install process checks that your system meets the minimum requirements; if they are not met, Dragon NaturallySpeaking will not be installed.
• CPU: minimum 1 GHz Intel® Pentium® or equivalent AMD processor or 1.66 GHz Intel® Atom® processor. We recommend 1.8 GHz Intel Dual Core or equivalent AMD processor. (IMPORTANT: SSE2 instruction set required)
• Processor Cache: minimum 512 KB. We recommend 2 MB.
• Free hard disk space: 2.5 GB (2.8 GB for localized non-English versions)
• Supported Operating Systems:
o Microsoft Windows 7, SP1, 32-bit and 64-bit
o Microsoft Windows Vista SP1 and SP2, 32-bit and 64-bit
o Microsoft Windows XP SP2 and SP3, 32-bit only