Claire was not pregnant with Charlie's baby, though he treated the child as if it were his own. In S01E10, it is shown that the father of her child is her ex-boyfriend Thomas.
I believe you're looking for Charlie's GreatesatGreatest Hits, which was a list of his Top 5 memories. That list was supposed to be delivered to Claire in the event he didn't make it back.
- #5 - The First Time I Heard Myself On the Radio
- #4 - Dad Teaching Me To Swim at Butlins
- #3 - The Christmas Liam Gave Me the Ring
- #2 - Woman Outside Covent Garden Calls Me a Hero
- #1 - The Night I Met You