Hello M Sev.
I understand you are having multiple issue when trying to install the full feature software for your Laserjet 100.
I've done some research on your installation issue, and I have found a HP document that should fix your issue. Please click here: Fatal Error 1601. Even though this document is referring to Windows XP, most of the steps can be applied to Windows 7.
Also are you connecting this printer wireless or USB?
If you have any other questions please let me know and I will be happy to help you.
Ashley