DF is correct, you cannot access the files to do anything with them without being rooted, for the most part. You can do some limited pushing and pulling of files with adb on the pc, but you are not gonna be able to do much more than fiddle with boot animations, I believe.
I am trying to remember, but I think Astro File Manager may let you see some of your phones files, but it has been so long since I used Astro unrooted, I do not remember exactly. Again, you are not gonna be able to do anything with them if Astro works.
Craig