Transitioning from Windows 2000 Server to 2007 Server

Our Domain Controller is on a Windows 2000 Server Platform. Exchnge is also on a 2000 platform. We how several file servers currently on 2003 Server.

I want to upgrade everything including Exchange and the DC, to at least 2003 Server. I would like to completely transition to 2007, but have heard horror stories about moving up 2 platforms. Can I even go from Windows 2000 to Server 2007, or should I just move everything up to 2003 Server?

jho