Trouble copying and pasting between Excel and Windows

I have just bought a macpro with snowleopard and parallels 4. I could not get a copy and paste from Grab to the windows xp side. The only thing I can get working in copy and paste is copying text from Office 2007 Word for mac to Office 2007 Word on the windows xp side. This would not work for a picture!! As a new user of macs, what am supposed to be able to copy and paste from one side to the other?