http://www.chess.com/forum/search?keyword=free+engine+gui
Best free GUI and Engine for Analysis

ChessX or Scid vs. PC.
Also worth noting is Lucas Chess. Wouldn't touch anything else with a 10 ft. pole because of your "easy to use" clause (especially Arena).
All of these come with an engine/engines ready to use. If you want the best, get the latest Stockfish (either the best in the world or close enough that it doesn't matter and it's totally free).
Hello,
Please advise me on a free Gui (easy to use) and a good free engine to analyze my own games.
Thank you