U can secure your computer more,and speed up browsing,and stop certain sites from loading,or site types,by using a custom DNS.I use openDNS which i've used for a while now,and works well.Go to openDNS site and it will tell u what to do,is quite easy and doesn't take long,and is free.U get ur own web page where u can customize settings and look at your browsing stats amongst other things.I think its brill for free.It's a service u would expect to pay for.
Commodo do one aswell,but not so comprehensive,just secure.Just put 156.154.70.22 and 156.154.71.22 instead of the 208.67.222.222 and 208.67.220.220 for openDNS.
These numbers might not make sense now,but once u've looked at the openDNS site,u will know what they are.
http://www.opendns.com/start/