A:
Surface has a full, real web browser, full, real Office, and full, real Flash. iPads have none of those things. Surface is also MUCH MUCH better at multitasking. It can also be used as a notebook or even desktop, and has a full desktop.
It also has a real file system, just like real Windows (or OS X).
It also has good scanner and printer support. Probably not as good as full Windows, but when I set one up for a relative, it automatically grabbed drivers for her existing printer and scanner from Windows Update and works just like real Windows does with them, whereas they wouldn't work at all with an iPad.
Basically the only advantage iOS has is if you have a specific need to sync with iTunes, or specific programs available for iOS but not from the Windows Store.
Surface can do a LOT more though, and for some people actually function as a primary PC.