No, you can’t change the size of your computer screen, but you CAN change the size of Windows ON the screen. This “windows size” is typically called Screen Resolution, and is a measurement of how many pixels wide and how many pixels high your display is set to.
In modern computers, most standard screens are set to 800 x 600, 1024 x 768, or 1280 x 960, but there’s a large variation in these numbers since many newer LCD monitors are wide screen.
Why would you want to change the screen resolution? Displaying more pixels on the screen allows you to “see more” of what you are viewing.
Although this isn’t a big deal with most application programs (like Word or Excel), it can be a big deal on the Internet. Many new web pages are designed to best fit on higher resolution screens, which means that you may have to not only scroll up and down to see the page, but also back and forth. So to make your viewing more enjoyable, consider changing your Windows screen resolution to best fit whatever it is you are doing.
And to help you out, here’s a how-to video you can watch.