Click the start button and select "run," which is on the left side of the menu.
If for some reason this option is not there, create a new text file with notepad and type "command.exe" (no quotes) in...
START > PROGRAMS > ACCESSORIES > Command Prompt
Its not exactly DOS, bot it is the closest thing within the XP OS.
For a MUCH easier shortcut that anyone can remember....
WINDOWS KEY + R...
An application called SYSTEM could have failed another application that ALL computers have is SYSTEM IDLE PROcESS that could also have failed.
another thing is viruses they can do this to you to a...