Puzzle of the week #142

Chess Diagram: 

[Event "Puzzle #142"][Date "2010.11.23"][Result "1-0"][SetUp "1"][FEN "3k4/1p6/1P1K4/2P5/8/8/8/8 w - - 0 1"]

Have you heard of the expression "Still waters run deep"? It basically means that whatever you see on the surface can be misleading, so in order to come up with the right decision, you need to look beneath the surface for all possibilities. For some reason this is what came to my mind meantime I was solving the puzzle. Now let's see how deep can you go!
This looks like a straight forward opposition case and looking on the surface it seems that Black can easily hold it. On the other hand White has an extra pawn and on the surface this should give White an easy win, right? Your task:
a) White to move; choose the best continuation while deciding if White can win or not
b) Explain your solution

Total available points for this puzzle is 20. The answers will be published next week together with puzzle #143.

Puzzle #141 solution:
Game: Sagar - Healy, 1979 Facebook. Only a few of you are still solving puzzles on a weekly basis and of course only you will see the benefit of doing so in the long run. I was a bit disappointed as I was hoping to get only correct answers based on the simplicity of the position. Karl got it nicely with the following answer:
Material: even. White has a Knight for a Bishop.
King safety: the Black King is significantly safer. Many of the Black pieces are pointed towards the White King while the Black King isn't even attacked!
White positives: not much.
White negatives:
- Nc2 and Rf1 are a little bit cramped.
- many pieces have low mobility
- Weak position: bad defense
Black positives:
- attack on the White King
- mobile pieces
Black negatives:
- Ba7 is a bad bishop
There's a pawn chain a little bit to the left of the middle. This is an attack/ defense on the King-side position. But it all comes down to calculation.
b)See solution:

[Event "Puzzle #141"][Date "2010.11.15"][Result "0-1"][SetUp "1"][FEN "r4rk1/bp1bq1pp/p1p5/2Ppp3/1P1P2n1/4BN2/P1N2PPP/R3QRK1 b - - 0 1"]1...Rxf3 {A nice sacrifice to start the attack, eliminating an important defender} 2.gxf3 Qh4 {Threatening mate on h2} 3.fxg4 Qxg4+ 4.Kh1 Qf3+ 5.Kg1 Bh3 {And now mate is inevitable. Is this the solution? It seems simpler than the many before it. Eugen: Yes, this is the solution. Aparently it was not as simple for everyone else...}

Correct solutions:
Karl - 20 points
Alex, Jeffrey - 5 points

Karl - 269 points
Jeffrey - 230 points
Rick - 174 points
Frank - 122 points
Alex - 106 points
Owen - 95 points
Edwin - 72 points
Nathaniel - 60 points