HELP! How do I get to fill the screen on my monitor?

My old computer finally gave up the ghost, and I had to get a new one that was preloaded with Windows 7 Pro (I hate it, but that's another story). One thing that's making me bonkers is that I'm at a loss as to how to make everything fill the monitor screen. Whether internet pages or desktop photos it's acting as though I have a teeny tiny square monitor and nothing is filling the monitor screen. It's also making me nuts that text is microscopic and everything is smooshed looking as if the normal rectangular view that I used to have got squished in on the sides so everything is looking tall and skinny. Here's a couple of examples of what it looks like...







This is particularly crazy making with my calendar in WordPerfect.

Any help would be greatly appreciated (before I'm bald from pulling all my hair out)!