Ouch. Ok, if you had so many apps installed that depended on "python", that probably means you had all the Python you needed already on-board, and your issue may be different than mine.

Hmm. Alright, well, try this:

apt-get install python-hildondesktop

Then reboot, then reinstall the applet. (Keep in mind, I'm mostly guessing here, based on vaguelly similar experiences... I'm not an expert on this issue by any means.)