When I first purchased this HP laptop it was pre-installed with Win Vista, It was later upgraded to Win 7 from (upgrade) disc. Presumably the pre-installed "recovery" D drive contains (since I didn't have recovery disc(s) with it) the original Vista. Can the Vista be deleted and the D drive merged with the C drive without upsetting the rest of the PC?
Experience; is something you gain, just after you needed it most.
When faced with two choices, simply toss a coin. It works not because it settles the question for you. But because in that brief moment while the coin is in the air. You suddenly know what you are hoping for.