Right when the DELL logo disapears, press F8 several times to to force the bootup menu. Try the "restart computer with the last good known configuration" first to see if it comes back to normal. If not, repeat process and restart in "safe mode". If not, then next time start on "safe mode with command prompt". If any of these last two boot you up, run chkdsk (check disk), and reboot. If none of them work, then, when you restart and the DELL logo is on, and at the top says "press F3 to run setup" and "press F12 for bootup options", press F12 and select the last choice which will be something like "dell diagnostics" or "alternative boot up partition". Then run diagnostics on the Hard Drive for physical damage. If the HD is bad, is going to throw an error code. To which you will have to buy another HD.
A good firearm, is the one that puts food on the table.