Habits are easily broken and systems are easily compromised by not sticking to a routine.
Always use custom install,
Always. What to uncheck depends on how you use your system.
If you only use on-line email like gmail, hotmail, etc, then you don't need the MailShield
If you haven't paid for SecureLine, you don't need it.
If you don't intend to purchase Grime fighter, you don't need it.
Avast! Gadgets
I don't install it - up to you
Browser Cleanup - Gets rid of Toolbars and other PUP's
Your computer so some choices have to come from you.