ok, so my nephew who is five years old was using my computer, and when he finished, i saw that the resolution was stretched too much, but only on the center, and too narrowed on the edges, so when i try to move something around the screen, it stretches only on the middle of the screen, and appears too narrow on the edges of the screen. also, the display was too wide so that i cant see the rest of the display (the edges, such as scrollbars, the X button, etc.) so i tried to tweak with the monitor's settings, but then above problem happened (stretched center, narrowed edges). i attached a screenshot to help.
i asked him and he said that "he pressed something" to make it happen, and i can't figure out how to revert it.
the stretching/narrowing only happens on resolutions beyond 800x600. i am on a samsung LCD monitor.