Windows 8 changes a lot of that....
On my computer with Windows 8, it take 5 secs to boot. Close enough to instant for me! I'd say check into Windows 8 to see what has changed for yourself - ignore the naysayers and keep an open mind and you may be amazed.
I too have a mix of mobile and desktop solutions. Each has its place. Mobile devices just allow us to work more often, not work better. Is that really a great idea?