DaCrust:
I have no idea what the rest of your academic
career has been like. If all your other classes have been As than you can get away with this D+ and say it was just a fluke.
However if your academic record is far from exemplary, every little thing will hurt you down the road and you shoudl seriously consider gettign this D+ off your record.
But don't assume that retaking a class you have already taken will get an A automatically, make sure to work really hard, and do your work.
Arti
P.S. If you are like the rest of us mortals, don't think Calculus II will be an easy way to get an A, unless you are a math major.