Try this....
1)goto start menu -> click on run
2)type "msconfig" and click ok
3)on the general tab select "normal startup" click ok, and restart the windows.....

hopeless gramma -
move your mouse to the bottom of the screen. Does the taskbar now appear? If not, press CTRL-SHIFT-ESC to bring up Task Manager. Now click on FILE - NEW TASK - and type
explorer.exe and press ENTER. Then please tell us how all of this started.