Can you tell us which browser(s) you're using? And have you tried clearing the browser cache? It's possible that there's a conflict with your DNS resolution; I'd clear that as well (DNS cache). I doubt it has something to do with the script on the site, which is why reinstalling abode was...
Did you actually delete the message, or just archive it? If you were viewing the message and just hit the X, the message would have been archived and is retrievable. But, if you selected the message and went to "actions-->delete conversation" it's gone forever.
If you did just archive the...
Me personally, I would learn HTML4 before moving to HTML5. HTML5 is pretty new and technically is still in draft, whereas HTML4 has been out since the late 90's and is extremely prevalent.
Comparing the two, HTML5 is definitely more powerful and flexible, is better at error handling, offers...
Sorry, but unless you've downloaded and set up an app that actually allows for you to track your phone online, such as "where's my droid?", you won't be able to recover your phone. Cell phone carriers won't be able to assist you either.