These screenshot from duokan.com show what I see when booting up in a Kindle 2i. Incidentally, I tried the #3 selection, and it just booted into Kindle:
http://duokan.com/forum/thread-273-1-1.html
Here are other screenshots that show pdf menu in Chinese -- it looks the same in English.
http://duokan.com/forum/viewthread.p...&extra=&page=1