MAC OS X instead of Ubuntu

I have an ACER laptop with an Intel 2.0 Ghz CPU and dual-boot (Vista and Ubuntu) I know how to boot ubuntu from an USB stick, so I would like to uninstall ubuntu from my PC and then install OS X.(I want to have it dual-boot OS X with Vista) Should I uninstall Ubuntu by deleting the partition?(Will the GRUB loader be uninstalled if I do????)Can I run the iPhone SDK on OS X?(I have an Intel CPU)


Thanks!:)

How much RAM?

I'm not sure how it works with Vista, but when I uninstalled Ubuntu on my XP PC, I just deleted the partition and used an XP recovery disk to access the recovery console (or whatever it's called).

If I'm not mistaken, all I had to do was type "fixmbr" and it fixed it. I could be wrong though, that was awhile ago.