Hard drive installation

Hello,
I have just purchase a laptop with no cd-rom and no floppy drive. Does any one know how I can boot this system? I have hard drive that I uninstalled from my other laptop when I upgraded the hard drive and it should still have the operating system installed. However, the computer that I have purchased is not the same brand as the one that the hard drive came out of. I know that the hard drive is formatted to my other laptop; when you format a hard drive does it format specifically to the system that you will be using or can you format it and install in into any system.