hide others?

If the program is open among many apps, clicking option-command on that app in the Dock will bring it forward and hide all others.

Command-tab will let you see what apps are running. You can tab through this "heads-up screen" with the command key held down. (This is the same as four finger swipe horizontally.) You will still have to click to bring it forward.

There are of course many keyboard shortcuts that you might find convenient as well: http://support.apple.com/kb/ht1343

hope this helps

I think you are transporting too much windows-like behavior into the Mac world, because to me it sounds like you are using your apps fullscreen, which is not the way OS X window management is intended to be used (and, to be honest, is a real bad habit from windows OS.

anyway, I don't want to get into a window management discussion here. OS X intends you to use your apps in "small" windows (basically just the size you need them, which is what the green plus in the top left of each windows does). if you do it that way, you can easily switch between windows by just clicking on them. additionally you can use spaces to manage a lot of windows

You might try looking at this exposé & spaces tutorial:
http://www.apple.com/findouthow/mac/#exposebasics

You received the info on how to do the windows thing on a Mac. The Mac paradigm is whichever app you last launched gets the focus; otherwise, no reason to launch it if you don't want to use it.

Once you sort this out, see:

Switching from Windows to Mac OS X,
Basic Tutorials on using a Mac,
Mac 101: Mac Essentials,
Mac OS X keyboard shortcuts,
Anatomy of a Mac,
MacTips, and
Switching to the Mac: The Missing Manual, Snow Leopard Edition.

Additionally, *Texas Mac Man* recommends:

Quick Assist,
Welcome to the Switch To A Mac Guides,
Take Control E-books, and
A guide for switching to a Mac.

Is there any way to have snow leopard default to hide others?

Not per se, no... I believe that you can accomplish this through some of the features of parental controls, but I assume you don't want to hobble yourself with that just to achieve this effect.

One thing you can do, which I use frequently, is to hold down option when switching apps. This has the effect of hiding the current app before switching.