Try a System Reset:
Hold down the on/off switch and the Home button simultaneously until you see the Apple logo. Ignore the "Slide to power off" text if it appears.
A System Reset does not remove any apps, music, movies, etc. nor does it cause any settings to revert back to default.
Also, you might wish to download the iPad-2 User Guide. Pay special attention to page 162. Note that this Guide also applies to the iPad-1 with IOS 4.3 except for those functions that are not supported by the hardware.
http://support.apple.com/manuals/#ipad
Finally, the User Guide can be downloaded at no charge via iBooks and a less comprehensive version of the Guide is included as a Safari bookmark.