I don't like windows 8 on non-touch laptops, FWIW. But if I had to make one choice out of all of them, windows laptop FTW. I currently own a lot of computing devices since I'm constantly upgrading to stay up-to-date for work, and the one thing I rely on the most is my laptops. having upgraded through five different laptops in the last 2 years...I rely on them for nearly everything involving work and entertainment when out of town.
If I had to choose a tablet, I'd choose the windows tablet. Ipad's are not a proper business tool IMO, their OS and features are too cheesy. Android tablets would take a cloooose second here
If i had to pick a phone, it'd be the windows phone devices. Having used everything under the sun as far as phone OS's go, the best one on this list goes to windows. It's the only one that has the things I need on a daily basis withing the fastest reach, and is completely compatible with all windows formats. The best Phone OS's of all time go to Symbian(many don't like it bc they're too stupid to figure its advantages out) and Maemo/Meego(also not for your average idiot, but AMAZING if you have used linux)