Problems in the Orchard

The extent of my gardening experience is cutting grass and tending a few pots, then 18 months ago found a house with a fairly large garden and a small orchard, 2 Pear trees, 2 Apple, 2 plum and a cherry, no idea on varieties. This year so far plum seems to be doing quite well, cherry had loads of blossom doesn't look like it will have much fruit. leaves on 1 Apple are curling and the other is starting to get covered in a grey fluffy mould but the focus of this post are the 2 Pear trees both of which have yellowish/red spots on the leaves. I believe this is Pear rust, after looking at other info on the internet the advice seems to be pick off affected leaves and burn them. The problem with this being there wouldn't be a leaf left, any other advice gratefully received