No you don't need to root yet.
Choose a wallpaper you like, go for a blank one for the time being so that you can get used to icons and designs.
For the bar at the bottom adjust the shortcuts to something that fits you better, LP (launcherpro) has some icons built in so you can change those.
If you don't like those just search online and find icons you like, and use those as custom icons.
When it comes to app icons, you can keep them standard which is just long press the app on the app drawer and it'll go to your homescreen.
Or you can again find icons online, and use a program like Better Cut, Folder Organiser (the one I use) and change the icon in the program. Then create a shortcut from Folder Organiser.
Hope that helps a little