Here are my suggestions:
1) Use a good quality paid Antivirus (not Internet Security Suite version) such as Webroot, Nod32, Kaspersky, or Emsisoft
and if not using Antivirus that is also AntiMalware as Emsisoft and Webroot are use Malwarebytes Pro as well.
2) "Web of Trust" on all browsers (WOT).
Safe Browsing Tool | WOT (Web of Trust)
3) "Ad Block Plus" on all browsers (keep out Internet Ads, not just popups)
4) "Win Patrol" on all systems free or paid version ties down startup, home page and registry
www.winpatrol.com
5) Practice safe surfing. Don't open email attachments without knowing for sure who sent it and why and stay away
from any websites WOT warns against.
6) Keep all plugins up to date i.e. Adobe Flash Player and Reader and Java (and I can't imagine how to do without these as almost every website I use needs one of the other.....
7) Backup whatever is important to you to either an external or internal hard drive or cd-dvd away from pc
I have 5-600 clients including businesses as well as home users and have never seen an incidence of ransomware yet up close!