It's a bit like looking for a sat nav and a digital camera all rolled into one. I'm sure such a thing exists somewhere, but why the hell would you want them combined into the same device?
Rather than be looking for the "best buy" you can get, and getting blinded by technical detail re specs, first ask yourself:
(a) what do you want to do with it?
(b) where and when would you typically use it?
(c) how much do you want to spend on it?
If you mostly plan to work on Microsoft Office documents, forget about tablets (or anything touchscreen). You'll be much better off with an entry-level Windows 7 laptop with a decent keyboard. €300-ish will get you plenty.
If you don't plan on typing much and just want to browse the internet, watch videos and check emails, then an Android tablet is a good choice, but decide whether you want a bigger screen, say 10" (which will have a shorter battery life and be less portable than say, a 7" model), etc. These start at <€100 but a reasonably good one will be closer to €200/€250.
If you really, really want "an all inclusive tablet/laptop rolled into one", there's the Asus
Transformer Prime 
series, but you're paying a premium for the gadgetyness factor, IMHO. A normal laptop and a decent pocketable tablet (or a smartphone) seems to work better for me.