Website Hacked – Plugin advice

Hello everyone!

All my wordpress sites were hacked and only Enfold theme keep working even when the hacked file was on the server ( in the enfold theme folder).

I have BackUpWordPress and I was able to recover all the sites!
I’m not a wordpress expert but I have installed about 20 wordpress sites!
Now I understand why keeping the plugins/themes and wordpress up to date is very important!

My question is what are the best steps to keep my site secure?
I was thinking about buying one of these security plugins?

Hide My WP – No one can know you use WordPress!
http://codecanyon.net/item/ (Purchase code hidden if logged out)(Purchase code hidden if logged out) /4177158?s_phrase=&s_rank=10

Security Ninja Plugins Bundle

http://codecanyon.net/item/security-ninja-plugins-bundle/8926745?s_phrase=security&s_rank=4

Thanks for the help!