Screen size weirdness Help!

I know this is not big problem but its driving me nutz ! When I use the pad it sometimes changes the screen size and its huge and I cant get it to go back to normal . I can't use 2 of the most important pages I can but its ridiculous .Any thoughts about why its doing it and more important how the H do I fix it ? ....

 

You're probably using two fingers on the mousepad and activating pinching. Try it on purpose, put two fingers on the mousepad and spread them apart, the resolution should increase. Now pinch them back together and the resolution should decrease. Pinching can be turned off in the mouse settings in the control panel.

 

Thank You ! I knew it wold be something simple ...I think I like it now