Part of my touch screen phone isnt working the bottom of the screen just wont work at all what shall i do?!?

hiyaa, i have a samsung tacco, and the whole of the bottom screen where it says stuff like (back and confirm etc) i just cant tap it no matter how hard i pressed it ive tried leaving the battery out for a while and charging it but nothing has helped its been like it for like 3 hours now please i need my phone i need to read the messages but it wont let me even click on them please help?