Replying to Computer help

i hav a dell laptop, and i ned ns's help. i turned my omputer on this morning, and verything loads except the start bar on the bottom of the screen. so, i turned my computer off, and pressed start windows normally. again, the start bar did not come up. so when my computer was starting up again, i pressed reboot, and now everytime it gets to start windows normally it goes right back to the screen that comes up when you turn on the computer. does reboot mode like stay until you turn it off or something? and if so how do u turn it off. idk somone please help me!