I'm lurking with intent as I have the same dilemma. Also have oak flooring in the hall and pale yellow walls! I quite fancy a stripey stair carpet but can't find one I like. Also I have no idea what to do with the landing.
I like those stripes Simon. I've ordered an assortment of grey, stripy & beige samples from John Lewis & Carpet Right. Fingers crossed we agree on one of them, though I'm having second thoughts about the yellow now it's up