Help! CPU keeps restarting at Welcome page!

Hello,
okay! im completely frustrated. I am no pro when it comes to computers, but this is what i know.

My comp is like 6-8 years old. It worked fine yesterday until it got to a point where there was a massive lag during my turn off computer period. So stupid me decided to hold the power button until its shut.

Today when i turned it on, it brings me to the Welcome page in windows xp (professional?) an then it suddenly restarts. Brings me again to the welcome page, and restarts. Then again and again until i shut it off. I tried entering the safe mode, but it didn't work. Still restarted. So i got into the configs.

I realized that the Second Dvd drive was not working properly. It says that they cannot detect secondary drive?
So i tried opening the dvd drive. I pressed the button and all i experience was the dvd making noice and it did not pop out.

That is really all i know. PLease help!