Yes, she'll be able to use those Adobe programs, but only if you got a tablet or device that runs Windows 8 (Windows 8.1 which it is now). Windows RT does not run any Desktop based programs like Photoshop, Dreamweaver, Thunderbird, etc. If you got a Windows RT based tablet it would only run apps from the Windows Store, so as she wants Desktop based programs it will have to be the full Windows 8.1 that she would need.
Surface Pro 2 is a great top end device, I hope to get one myself at some point. Surface's are more than a tablet as they can have a touch or physical type cover attached, have the kickstand at the back and supports a digitizer pen. It really is a high end laptop crammed into a tablet format, so you have the power underneath to use it as your main machine.
There are quite a few tablets out there with Windows 8 on now which is good to see. If she is running the likes of Photoshop she would indeed be better with a higher spec'd one like the Surface Pro 2 which you mentioned or something like the
Dell Venue 11 Pro which can come with Intel i3 and i5 processors. This also supports a digitizer pen if she wants to use one and a keyboard which you can attach to it (these are additional to the cost of the tablet).
There are also many different laptops that could fit the bill, with being fairly slim and powerful, but obviously she will always have the keyboard attached. If she wanted something really portable, the Surface Pro 2 is probably the best choice.