Right-click Context Menu

Is this a wired or wireless Mouse?
Is there any third party mouse settings program installed?
Have you checked under this or the general mouse settings to see if there’s a ‘swap mouse buttons’ box where the left button & right button are exchanged - this is usually for left handed users so the left button becomes the right button for them & vica versa?

vanp said:

I click on ads on some websites and gadgets to give revenue to the service provider. Generally, I want to right-click, then click on 'Open Link in New Tab'. More and more, right-clicking is acting like left-clicking and taking me to the ad site in the current tab or doing some other action I don't want.

Shouldn't right-clicking always produce a context menu, or not, or is my mouse messing up (bad mouse!)?

It shouldn't. Right (and left) click acts as a site or app developer wants. What you see is normal.

PS: You may avoid some (not all) annoying clicking actions using proper addons in your browser, like ad and/or popup blocker etc...