Mark, I'm really a novice with the Mac. I also use Outlook etc, but still love the Mac. I purchased a copy of Office Mac 2004 through the company in Dec, and it's brilliant. I just ordered Office Mac 2008 via work ($37.00) and got a call from Fedex telling me it's arrived (I'm away on hols at the moment). I migrated all my Outlook stuff across to the M$ Office Mac equivalent (Entourage) and it is actually easier to use than Outlook (IMHO).
As Kelvin wrote, there are a few apps that will allow you to run Windoze. I never tried VMWare so can't comment on it. MAC OSX also comes with Bootcamp which allows you to boot an Intel Mac into Window$. Parallels and VMWare allow you to run both concurrently. I chose Parallels mainly because a lot of guys at work use and recommend it.....
I have a licensed version of Win XP so the only cost to me was the Parallels software (about $99.00) All the Win apps that I run on the Mac are licenced copies, so no additional cost to me
I can only give you a subjective response on its performance, but XP seems to run a lot faster on the Mac then it did on my old Toshiba notebook.
Hope this helps.