Running Homemade Operating System
Starting out with an operating system you wrote, how could you run it and test it on a computer? Would you have to delete the current operating system that is being used, or could you run one separately?
Solution 1:
The easiest way to run or test new OS, whether or not it is home-made, without deleting current operating system would be to virtualize it. You can use free and commercial tools for that. Best known are VirtualBox (free), VMware Player (free), VMware Workstation (commercial), Windows Virtual PC and so on. You can find much more on Wikipedia Category:Virtualization software
Basically, you create a virtual hard disk image which behaves just like a new, blank hard drive. When you install operating system it is within that disk image entirely being totally isolated from your main operating system. Aside from testing and booting an operating system you can also test various programs within an isolated environment. There are many possibilities so I recommend you explore that area.
Solution 2:
I used to use bosch for emulation back when I was playing around with OS development. IIRC I followed this tutorial: http://linuxgazette.net/85/mahoney.html