Try this: Hold both the power and home buttons until the screen goes dark and the Apple logo then appears (the slide to unlock screen may or may not appear). Once the logo appears, release the buttons. After a time, your homescreen will appear. Please note that it may take some time for the Apple logo to appear or for your homescreen to appear (or both). This is normal. Eventually, the homescreen will appear.
The iPad may have just gotten "stuck" and this procedure usually works to UNstick it. Good luck and let us know how you get on.
Marilyn
P.S. I've deleted another post you had created for this issue. Not only does having more than one post fragment the conversation and make it hard to follow, it's also against the forum rules. So, please use just this thread for any follow ups or updates. Thanks.
P.P.S. I've also moved this post over to our Help section where a lot of experts hang out. Maybe they can also be of some assistance. Thanks for your understanding.