For starters, stay with mainly the default settings and only harden up a few things. In the Firewall, leave it on Safe Mode and uncheck creating rules for safe applications, and uncheck not showing alerts. Set the alert frequency to low.
In the AV settings under real time scan, uncheck do not show alerts and auto quarantine. Set heuristics level to low
In Defense+, Leave the Behavior Blocker on partially limited or Limited at the most. Do not enable HIPS
Fully use the trusted files and trusted vendors lists under File rating settings. Make sure all the boxes are checked.
In short, Firewall in Safe Mode, AV in Stateful, Behavior Blocker on Limited, and use the Internet Security configuration as is the default. If you have already switched to Proactive, switch back before changing any settings. The small alterations from the default that I suggest will give you more security but maintain ease of use and limit necessary interaction (replies to popups) to a bare minimum. You will have very few issues with using or installing any safe applications but will be alerted to things that are unknown to the system and possibly harmful.
As you acquire more savvy in Security issues, you may want to harden things up more, but for now you want CIS to do as much as possible for you and remain silent and in the background while it is doing so.