I cannot seem to download or install the latest driver through the HP website. It just guides you to do the apple update process.
This is what is listed under system report:
hp photosmart 7900 series:
Print Server: Local
Driver Version: 1.5
PPD: Generic PCL Laser Printer
PPD File Version: 1.5
PostScript Version: (3010.000) 0
CUPS Version: 1.7.1 (cups-372.2)
Scanning support: No
Printer Commands: none
Fax support: No
Did you try Software Update?
You're using a PCL driver, so that explains why you're not getting the printing options.
You can download the drivers here: http://support.apple.com/kb/DL907
If you did a clean install, that would explain why the drivers are missing.