First things first. Obtain root. Obtaining Root | Root Your Droid This will not change or remove any of your settings.
Second, set up ADB. Android Debug Bridge | Root Your Droid You need this to do much of the stuff you want to do.
Next, set up Sprecovery. Custom Recovery Image | Root Your Droid You need this so that if anything you do hurts your phone, you can restore it. Again, this will not remove or change settings
Then you need to backup with Sprecovery. Full System Backup Using Nandroid | Root Your Droid You can restore this is ever need be. Again, this will not change/remove settings
Ok, now we can get to the fun stuff.
Wifi Tether/Overclock http://www.droidforums.net/forum/dr...ss-tether-patcher-one-click-solution-2-x.html This will not remove setting/layout. Also, this tells you how to root and install sprecovery and such, but it has old files for that. Use the links I provided. Skip down to step number 4.
Busybox Install Busybox | Root Your Droid This allows you to do many other things, including add themes.
Custom Roms http://www.droidforums.net/forum/android-roms/18871-droid-rom-links.html This WILL remove all of your settings and layouts!
Hope this helps. Have fun!
OK I just did everything up through the backup. I want to keep a copy of the backup on my PC. What is the location of the backup on the SD card and what is it's name or names?