It sounds like it's the Easy Install, but you can find out for sure in the panel for One-Click installs.
If your site was done in Advanced Mode, it will show up in the "Upgrade or remove previously installed software - Advanced mode" section (click to open this section up)
I don't have any Easy Installs, but I think you'll see a "Modify/Delete previously installed software - Easy mode" if this is how your site was set up.
Another clue would be in the Manage Domains section.
If the domain or subdomain where your site shows up as Fully Hosted, then it's an Advanced Mode setup. In that listing you'll see User: who has FTP access to the site. Click WebFTP if you want to see if your files are there and use that user's password when you get to the WebFTP screen.
Databases show up in MySQL databases:
There won't be much there to tell you explicitly what site it's tied to, but hopefully the little quoted comment below the database name will give you a hint.