Windows XP Professtional

I am trying to help my daughters teacher connect a printer to the classroom computer. The computer has Windows XP Professional installed. The printer is an HP Deskjet 6940.
I looked in 'Printers and Faxes' and saw that the printer software had not been installed on the computer. I installed it using the installation disk that came with the printer.
I cannot get the printer to print anything. Anything that I try to print goes to the 'Documents waiting to print' section. They stay there until I cancel them in that section.
In the lower right corner of the computer screen (on the taskbar, beside the clock), there is a snowman with a red, flashing X. I have double-clicked, right-clicked and tried everything to open this icon, but it will not open. It won't even show the little box to tell me what it is.
Does anyone have any idea what this snowman icon is?
Thanks.

 

Have you checked that the newly installed printer is set to be the default printer?

 

After I installed the printer software, I went to the printer control panel and the printer was not listed. I restarted the computer and then it was there. I selected it as the default printer. I tried to print, but it again went to the 'documents waiting to be printed' area. When I went back into the printer control printer, the printer was not listed. This was at 8 pm last night, (parents open house at school), so I wasn't able to do another restart. Have you ever seen the icon in the taskbar (lower right of screen) of the snowman with the flashing X? Every elementary class has this printer and they are all getting that same icon.