Simply press "menu" then go to "settings" then select "Sounds" then go to "Ringer Type" then at the bottom it will say "meeting/silent mode" select this then reselect it and your phone should have volume again and be off silent mode. Worked for me.
How Do You Get A Samsung Intensity Out Of Silent Mode?
You go to options, and then you go to volume, and then messaging.. And then you just click the volume up, and it should go off silent mode
I figured it out like the day after I asked this, but thank's anyway!