You're using the update feature in firefox itself? Or are you downloading the file from thier website?
I downloaded it from thier website last week (the same night they released it). The updates were released to the browsers (where you can check for an update from the browser itself) this week.
from the browser itself, wont update. I downloaded from the website... but now that I re-installed I gotta go through the process of re-installing all the plugins, but now I'm having the same problem installing the plugins, it just hangs...
Did you delete the Mozilla Firefox folder in your Programs Files folder when you uninstalled? If you did that when uninstalling, then you would have to reinstall the extensions.