pikey

I am brand new to underwater photography and I am looking for some advice/opinions on Intova cameras, specifically the intova sports 8, as well as any other brands people have found to have good beginner cameras.
I want something that I can use above water as well as underwater, and that has some adjustable settings (shutter speed etc) but not something that you have to be continuously changing settings to get a good picture. And something that is not extremely expensive (am willing to spend up to $500ish on a camera + housing)

At the moment I am using a 12MP Fujifilm and it takes wonderful pictures, but I find that if the light isnt quite right, some of the colours become really bright (sorry, not very technical description I know) or the picture becomes "grainy" when taking photos with the sun in the background/corner, or taking pictures where there is a bright light in one corner. Does this happen with some cameras, or is it just what happens when the light isnt very good? I havent printed any of the photos I've taken with it, so maybe its purely a computer monitor issue?

Any suggestions as to what brand people have had good/bad experiences with, and websites to check out to find out more information and tips on underwater photography will be greatly greatly appreciated!

Christine