HDD replacement help

You can use every HDD, even the ones labeled to be ready for Windows.

They are pre-formatted with NTFS, the file system Windows uses.

You need to format the HDD first via Disk Utility with the Mac OS Extended file system (HFS+), either while the HDD is connected via USB or inside your MBP.

Guide for Disk Utility: http://macs.about.com/od/applications/ss/diskutilformat.htm

Guide on the different file systems: http://guides.macrumors.com/Drives_and_Filesystems

 

As long as it is 2.5" and 9.5 mm high (1/8th height) and not 12.0 mm high (1/6th high), that's about the only thing you have to watch out for. But 12 mm high won't fit into most Windows laptops either.