Q: mac pro wont start

hi,

I have a mac pro and last night I tried to watch a movie on it but the DVD got stuck I switched the mac off and tried turning it on again but it wont take me to the main page after I entered my password to turn it on,,, the bar under the apple icon does not complete o 100%,,can someone please help me understand what might have happened to it. the dvd is still stuck in it. I tried shift + command + V but nothing happens after the black screen appears with errors like..

I don't have much knowledge about trouble shooting it so if someone can help that will be great.

thank you.