We are new to the IMAC, operating on Lepoard, comming from Windows. Problem, When I have Photoshop open the colors look differently than they do when I move the picture to a document like word or ipages. Also, the printed picture (Epson R200) also doesn't look the same as what is in Photoshop even with the latest drivers etc. Any suggestions?

I'd suggest calibrating both the monitor and the printer. You can calibrate the monitor from System Preferences -> Displays -> Color. Printer you can calibrate from the Print and Fax section in System Preferences.