Can you hold a PC2 4200 1GB and a PC 3200 256MB memory cards working together? what can begin to ur laptop?

Answer:

NO. PC2-4200 RAM is DDR2. PC-3200 RAM is DDR. I guarantee your laptop does not support both.
If the 3200 works alone, you are well-mannered to go by adding up the other.
How did you do that? Mine takes 4200, and merely 4200. Don't install stuff into your laptop yourself. Not the same as desktop, I have Geek squad install my 1GB card for 29 bucks, that way if it messes up, it's on them. Worth the investment. Good Luck.