Best line/ worst line of cameras? Also, 4MP vs 5MP?

Well, I'm finally deciding to take the plunge and go digital.

I've done my research about the technical stuff. The problem is, learning about all the techie stuff hasn't exactly helped me decide which brand to go with, so I just feel overwhelmed when looking at all of them. I have no idea how to narrow down my search brand-wise, whether to go Canon or Kodak or Minolta or what have you.

What are, in everyone's opinion, the best or the worst line of digital cameras? Meaning, those brands where you wouldn't think twice about looking at in purchasing cameras, as opposed to the ones where you're, like, "Yuck-- forget it."

Or is there no such thing? (In other words, all are good in some ways, but some are better at doing certain things than other brands, and it *depends* which ones are good or not, based on what you want out of a camera?)

One last question... What's the largest-sized, good quality print I could get with a 4MP camera? I'm asking this, because I'm wavering between getting a 4MP or 5MP camera. I'm getting the camera as a hobby; however, I'd also like to use it for family events and such. 4X7 is good, but I'd like to be able to print a little larger *just in case.*

Thanks!