Hi Matthias15,
bb has already answered your immediate questions, so I won't rehash any of that here.
GMAC has publicly stated that a Test Taker's Official Score is within +-30 points of actual ability, so these two scores are essentially the same (the Scaled Scores for the Quant and Verbal section are not significantly different from one another to imply that a big 'change' occurred - the likely cause of those changes are a handful of little mistakes - or making a bit fewer - in each section).
Either score is solid though - they're both right around the 80th percentile overall, so they might be enough to help you get into your first-choice Business School.
While I agree that you should take some time off, IF you do plan to retest, you shouldn't necessarily take a big 'break' from your studies. Much of the material is likely still fresh in your mind and you have the potential to pick up some big points in the Quant section (if you can make the necessary adjustments to how you 'see', and respond to, the Test).
1) How long did you study before each GMAT attempt?
2) What resources did you use?
GMAT assassins aren't born, they're made,
Rich