You could do a hybrid approach....
First.. get all the cards down to 70% or less utilization....
Then... go for highest interest first with the funds you have left to pay them....
You may not be able to attack both in the same month....
but once you got the balances below 70%... calculate the min payments + some more first, then use the rest in order of highest interest first....
So pay the min payment on all cards with some extra.. and then decide how your going to redistribute the rest of your payment amongst the cards...
That make sense?.. Not sure if im explaining it clearly..
(Grrr.. didnt see the post about the morgage... well.. pretend your savings is just an additional card... and put aside roughly a min payment for it as well.. youll need more but it will start you saving for a down payment, while working on increasing your score)
Edit: im out.. Youve already apped for the morgage.. and someone else is paying the down payment and other costs..
Snowball it or highest interest first.. if your going to try to pay it off in 6 months, it really doesn't matter at this point..