Error Message When Starting Parallels Desktop

Parallels 5 (build 5.0.9344)
Mac Pro Desktop
Snow Leopard (version 10.6.3 installed in Bay 1 of the Mac Pro)
Windows 7 (home edition installed in Bay 2 of the Mac Pro)

When starting up the Parallels software from the Parallels Desktop icon in the taskbar, I can choose to start the software with one of two options: My Boot Camp or Windows 7. Either way, when I start up the Parallels software, I receive the following error message: "Windows did not shut down successfully." Various options are presented to start up Windows 7, such as in Safe Mode, and to start it normally. Windows 7 does eventually start up in Normal mode, but the screen size is greatly reduced, and it is clear that the start up process is not working properly. The same result happens when starting up Parallels Virtual Machine in either "My Boot Camp" or "Windows 7".

Thanks for any tips on how to correct this Windows 7 error message in order to open Windows 7 with a full screen.