Ok, I'm a girlie and have/had both. Both TDi's and TD5's. They both have power steering, both tow well, I'd say there isn't much difference in space inside (ok, possibly the Defender 110 has more). If you are using it for the school run and family car, it has to be the Disco. They have more comforts than the Defender and much smoother ride.
I moved my smallholding in the snow, towing a trailer full of sheep no problem. Don't reckon there is much in it for fuel consumption either - they are both thirsty with a capital T. I have a love/hate relationship with my Disco - hate the fuel consumption and cost of maintenance, but love how useful it is. Mine has been reliable by and large (not the same for lots of Landy owners) - I keep threatening to sell it but somehow always need it and it's still here.
ALL Discos leak (get the sunroof sealed) but it is more comfortable than the Defender. So in summary, not quite as cool as a Defender but I'd go for the Discovery....