Security warning what does this mean?

[Glenn]

So i am useing a pandigital 7" media tablet powered by android, win first set it up it say to set up a gmail acount well I did but I use my hotmail acount, so win I go to a web page like facebook,hotmail,yahoo and other site i get a box that shoes up and its says this, Security Warning
THERE ARE PROBLEMS WITH THE SECURITY CERTIFICATE FOR THIS SITE.
then there is a red box with a x in it,THE NAME OF THE SITE DOES NOT MATCH THE NAME ON THE CERTIFICATE. What does that mean and how do i fix it so it don't do that no more,

AND sent I have you on here how do I get it.to and apps it. Say i need to down load java but it.tell me it can what can I do.so i can do the app thing and to.be. abl to.use youtube

[kenn d]

The security certificate thing is normally a warning to not continue the site could be trying to redirect you to another site entirely or could be trying to direct you to a FAKE or malicious site intended to harm your computer. If the name of the site does not match the name on the certificate then rest assured that means that there is something wrong and to proceed with the utmost caution possible.

[avapatch]

For YouTube you need Flash.

If you post your model #, I can advise.