Lovely paper, though it is quite a regular repeat so potentially could look a bit fussy with patterend fabric. Sounds like it could work, bit hard to tell without seeing the curtain fabric. Can you link to that? Which colour paper were you looking at?
You could always order a few samples of the paper (on different occasions), stick them together to form a good sized section of wallpaper and pin up on the wall and then hang your curtains. That way you will see if it works and you like it.
You could always use the paper somewhere else if you love it, perhaps in the downstairs loo, always a good place to use wallpaper. YOu could paint/paper the dining rooms walls in a lovely dark gold or red colour to bring our the colours in the curtain fabric. SOunds like you have a sophisticated scheme in mind.