Download K-9 Mail from the Market. It's free and gives you WAY more options than the regular native email application. You can change color of email among many other options.

You can also check the Market for several different types of keyboards, some with spell check. I use Better Keyboard and really like it.

Adjusting the screen timeout is a very simple process. Settings/sound and display/Screen timeout

I have an account at http://www.AppBrain.com makes it much easier to find apps and then have them automatically pushed to your phone and installed. Plus the search is much better than the Market's search. Makes it much easier than thumbing it all on your phone.

Utilize the search feature on the site. You'll be surprised with the results.