Yes, he is pleased since he states in a line that his decision made all the difference. He considers himself successful in life since he chose the path that led him to his intended goal. The poet merely regrets that he was unable to travel the opposite way as well. However, one cannot help but wonder if the speaker would have been equally satisfied had he not chosen any path at all. After all, there are many people who live miserable lives yet they still consider themselves lucky. Perhaps then, it is more appropriate to say that the speaker is content with his choice rather than successful. He is happy because he succeeded in reaching his goal. He managed to make all the difference by choosing what path to take and this fact gives him hope for the future. Also, it should be noted that the word "happy" has several different meanings depending on the context in which it is used. In general, though, to be happy means to feel pleasure or joy. Thus, despite all the problems he faces, the speaker remains confident about his future since he believes that he can find a way through them. This also suggests that even if you fail at first, you should never give up on your dreams. Keep trying new things until you succeed.