Create a new open source OS that is easy to use, and can use driver models from Windows and Linux. Make it so that it has a Virtual Machine which can run other Operating Systems under it. Port GCC and other languages to it. Try to port WINE so that it can run Windows apps without needing Windows, otherwise Virtual Boot Windows in a virtual machine.
And it must have a telepathic user interface! And be capable of time travel! And have a 42" screen, yet fit in a purse or handbag!