Uh-oh! A new computer comes to mind.........

Try this first, Make sure you UNchecked "hide taskbar" in OD then exit out of Object Dock......then restart it after your Tbar comes up. If that doesn't work (it should).....you should have a button on your keyboard with a windows flag or some strange symbol on it......usually on the bottom left between Ctrl & Alt. Press it. It should bring up your Start Menu and Taskbar. While it's showing right click on it and UNcheck Autohide. What may have happened is when you dragged it to the top you (accidentally) made it 0 lines high. If so you can grab the edge (click and hold when you see the up/down arrow) and drag it back to the right height.