Although I would have rather had MS Server 2008, the IT guys were familiar with MS 2003 (Std, with SP 2), so that's what we got, since I know (knew) nothing about administering a network.
I have to say I don't know when you set this up and I figure you have the right to yell at me and throw things at me if you want, but I just have to give my opinion as usual. Why would your "IT" guys install an OS from 2003 when it's 2011. SBS 2011 is already out. If they are truly IT guys, then they ought to be able to up to speed if they want to compete with the other IT guys. It's like having a car salesman telling you to get the 2003 model, because the mechanics are better acquainted with that model. That's why they send their mechanics back to school.
If you do upgrade, consider Small Business Server. It truly is a better OS for a small business and more economical. And, it is out in 2011.
Sorry, just couldn't resist.