Problems with Safari Loading Sites and Photos

For the past week (Feb. 2015) I've experience problems with Safari loading websites on my 2009 20" iMac desktop. Running version OSX Lion 10.7.3 4 GB. Intel Duo Core 2.66 GHz

Mac also will frequently not upload photos at websites like Yahoo News or Facebook. It does this throughout the day.

So, I downloaded Chrome, thinking it would be a better browser if Safari is not functioning. Chrome is just slightly better, and when it won't load a website I get the following error message from Chrome: DNS_PROBE_FINISHED_NO_INTERNET.

I'm debating taking the Mac to the Apple store for diagnosis or repair today, but if anyone else is experiencing similar problems, could you please offer some solutions as to what is going on.

Thank you.

AngieRK