Excel 2000 Shut Down Problem

I am running Office 2000 on a Windows 98 SE machine. I can open and work in Excel fine but when I go to close the program it just sits there with the hour glass. When I hit ctrl-alt-del a message comes up that I am “EXTREMLY LOW ON RESOURCES”, and that I should shut down programs. I can close individual workbooks with no problem it’s just when I go to close the program. My resources are fine before I open Excel. Any idea’s??