Screen problems

I am new here and I've had my galaxy s for about 4 months but now the screen frezes and the whole phone randomly shuts off or the battery goes from 95% to 5% in ( I timed it once) in 18 seconts. And now recenly the darned screen turned yellow!!!!!! Everything it a pale yellow and the back button sometimes continualy pressesit self for minuets at a time.  And then it electrocutes me! Its posesed by the demons of apple (lol, take te opprotunitys to diss iphone). I love android phones and they can survive anything, but this all hapened after I updated the phone

Any solutions? The yellow screen is incredibly annoying

~chaz

Um, I've got the key pad slid out, and I'm typing this with the touch screen. The dots have stoped.for.now.  I. Spoke. Too. Soon.  HELP!!!