If you haven't already done so (and even if you have!) turn the NC all the way off, not to sleep, completely off, wait a couple of minutes, and then restart.
Also clean the screen - they do all sorts of odd things if the screen is dirty, and it's amazing how many fingerprints and such they get! For me, the anti-glare screen protector helped greatly with it staying clean.
My nook color changes pages without me touching the screen. It will go all the way thru a book before it will finally stop on the last page. Help!!!
First put your NookC to sleep and clean the screen with a dry tissue. Many times that is the problem.
Did you put on a screen protector? I've never had a problem with mine and don't believe many folks have had but some swear that it could cause the page turn issue.
Third, always try the complete shutdown. Not just to sleep but turned all the way off them back on. "Rebooting." It sometimes does the trick even when there is no logical reason that it should.
Good advice on rebooting and cleaning the screen, bit I wouldn't use a tissue. I would use a lens or specialty screen cleaning cloth. Some tissues have abrasive fibers that could scratch the screen.
I have seen the page turning issue with dirty screens too. I also recommend the anti-glare screen protector. I use an LCD screen cleaner spray and a microfiber towel. Spray on towel not directly on screen. The NC screen protectors come with 2 protectors and a cleaning towel.