thaispetrucci,
You know what? I was thinking about this a couple of days ago while I was at work: Where does JP get his true inspiration for not only lyrics, but also for music? I spent some time coming up with possible solutions and I have to say that if one were to ask him that question right now, I'd bet that his answer would be: Family and friends. He's a devoted Husband and Father.
Speaking with the Uncle (Matt) of my Keyboardist, Matt shows that he's a changed man ever since getting married and having children. I don't have kids of my own, yet, but when I do, I know that my perspective on life will change. Think on that for a bit, go back and look at Petrucci's lyrics and also accept the fact that he reveals in his lyrics the true struggle of Man coming to terms with and accepting God as a major prescence as well as his internal feelings about his family and friends.
That's the solution that I've come up with. As to what lyrics impressed me the most, I can't really pinpoint which ones I like the best of all of them. I'd have to say that anything from 6DoIT were my favorite just because of the subject matter that was confronted when writing the album.
Of course, I also give credit to Mike Portnoy for working through his 12 steps and coming to terms with that. It takes a lot of courage to work all that out and I admire him for his strength.