My DELL (15x11) monitor screen is warped. Everything is elongated horizontally. How can I make it to normal?

Selecting the "Factory Reset" option can actually help adjust the screen image sometimes and it won't harm the monitor, so I'd say try that first. Then you should check the display properties/settings in Windows and try different screen resolutions to see what fits and works best for your monitor. It may help to find and install the specific drivers for the monitor to give it the best chance of operating correctly.