The second one looks good to me, Michael. It looks like you went in the right direction in your histogram adjustment. I like Greg's suggestion to reduce your DOF with that camera - but it brought up another point - did you use a flash? If so, it could be the reason for the "hot" or overexposed appearance of the petals. Natural light, through a window maybe would be a better option in a macro shot like this one due to a short distance-to-subject ratio that you can't control with a built-on flash. As for the background, If this is shot on a tripod, you could set the timer to shoot while you hold a complementary colored (black? green?) poster board or something in the background...

Tuna