dieki's questions

Ever since I reinstalled Ubuntu a few hours ago, I've experienced major visual artifacts with smaller font sizes in Firefox. The fonts end up looking like this:

Or even like this:

This only occurs in Firefox; other applications are unaffected. It also occurred on the LiveUSB I used for installation, making me suspect a hardware or driver issue. The output of lshw on my computer is here: http://pastebin.com/LnSt6veT.

Any idea what might be causing this, or how I can fix it?

... and "Use Google Chrome" is not a valid answer. ;)

How can I set the Software Center to allow non-root users to install stuff from the Ubuntu repos without having to type in their password?

I'm fully aware of the security implications, and I am willing to take the risk. Fedora 12 shipped with something like this. (By modifying the PolicyKit configuration, I believe)