My LCD display turns black and white

faulty connections in tv boards ie dry joint

Never, ever keep/expose the LCD display to direct sun light.
If you have done it, then you better get a new display.

If I understand you correctly, you're saying that the LCD display shows a normal picture when you are composing your shot, but that when you actually snap the shutter to record the shot, the resulting image has nasty lines across it?

That would indicate that the lens is fine, but that the image sensor itself or associated electronics have gone bad. If this is out of warranty, then you're likely out of luck.

Think that you might have accidentally pressed the DISP or DISPLAY button on the back of your camera. This manually turns the LCD display on and off to save batteries. You would then use the optical viewfinder in its place. To turn the screen back on, just press the DISP button one more time.

It sounds like the light sensor on the camera is malfunctioning. Try cleaning the sensor. If the senor doesn't work at all it will not be able to tell when the camera is operationg in bright light. Kind of like having your eyes dialated and walking outside on a sunny day.

I think that's normal. I also have experienced the same always when the screen is exposed to sunlight. Try adjusting its brightness or use an anti-glare protection.

the monitor is on its way out.
no fixes here. not worth the money.
you mention it is CRT. time to get a new one or go for LCD.

sorry to inform you guys but that is what the I40 and I60 do, if you take it in the DIRECT SUNLIGHT you will notice that it takes color pics ;-( bad design

The Display button manually turns the LCD display on or off to save batteries. If you accidentally had turned the LCD off, It should only take one press of the button to turn it back on and leave it that way. As such, it's not you but the camera. The A570 IS is relatively new. Your camera is likely still under warranty. If so, contact Canon for warranty repair (see the following link):

http://www.usa.canon.com/consumer/controller?act=PgComSmModDisplayAct&keycode=2113&fcategoryid=221&modelid=14905

You might want to change the white balance or bracket your exposures

Here is a link to the photonet site that may give you some things to try: Photonet