Delete Pop-Ups and pages with no "X" or cancel button

[Miss About to POP!]

How do I delete pages that do not have a "X" in the upper
right side of the screen or a cancel or delete button?

I am a new PC user and would also like to know if there
is a way to delete ( X ) a Pop-up that does not have a
delete/cancel button. Is there a way to stop the Pop-
Ups!

Any help will be greatly appreciated!
Thanx, Ab't to POP