You'd normally have a script as part of your shut-down procedure that stops postgresql/oracle - we'll need more information on your OS if you want more information than that! You _usually_ won't corrupt your database if you reboot the server with it running, but you'd be crazy to try it on a production server on a regular basis. :)
I wonder if your recursive /register call isn't the result of a permissions problem. This problem would occur if you'd perhaps messed up the permissions on the main site instance? (If you don't have permission to read /register, you get redirected to /register, which you don't have permissions to read, so....) If you made any changes to the permissions recently, that could be the problem. You'd need to manually grant The Public read permission on the main site instance.
If that sounds like what's going on (and you've recently muddled with permissions), I'd check in psql for a missing permission and replace it - if you need directions for exactly how to do so, please post and I'll dig mine up.
