|I have not found a business program that I can't get working so far. Might look into compatibility mode or other fixes first.|
My suggestion would be to use Microsoft's Virtual PC or Sun's VirtualBox software. Both free.
The applications are software versions of a computer. They run while booted into Vista. You then can install XP or almost any OS for x86. You don't have to dual boot or be worried about breaking your system. I feel it is the safest way to run XP.
You will need a valid XP disk.
Other suggestion might be to ask computer maker if then offer a downgrade DVD restore disk and also get the Vists disk that includes software back to OEM state.
Otherwise consider Linux running in virtual machine if office software has linux version or can be run in wine.
A dual boot for a beginner is likely to fail. At lest I have borked them more than a few times.
"Best Practices", Event viewer, host file, perfmon, antivirus, anti-spyware, Live CD's, backups, are in my top 10