Television and Home Theater

Hi, I am brand new to this... so please be patient with me.  I have an older GE 31" TV, the problem is 1st - I don't have original remote, but most important is the fact that the channels start at #51!  Is there a way I can reset this somehow?  I really can not afford to have a repairman come out and this TV is in good condition.  I have the serial number and from what I can read, anyway, the model number... serial # 425430166 and model # looks to be something like this " Z761617".. can someone help me with this?  I am at a complete loss. 

Ive browsed the forums already and figure out how to solve my problem but, when I try to move the red convergence to the left or right it wont move. Blue moved fine.

I have a Zenith Z19A11S it has a very odd problem.  When you turn off the power the sound shuts off but the picture tube stays on you can't change channels or anything but it seems something isn't telling the picturetube to turn off... Any ideas?