I don't know whether Disk Utility has been changed in any signficant way from mine to make a proper Windows partition. But whether it has or hasn't, you have two choices: booting into one system or the other using Boot Camp, or using a third-party program called Parallels that runs Windows inside a Mac window so you can run both at once.
Run a search on Mac-Forums (there is plenty on the subject on Mac-Forums), or on the Apple site (where everything is official), or on the web in general, using the terms "OS X" "Boot Camp", and "OS X" Parallels.
That about exhausts my knowledge of either of them.