I've got no complaints about my MIL, although I'm not particualry close to her. We don't actually see that much of her, although she lives closer than my parents - but that's dh's choice. It's not that he doesn't get on with her, it's just that we've got more in common with my parents.
She doesn't interfere, but is always there when you need her. But dh doesn't like asking her for help unless we have to a) because ds is her 13th grandchild and she has been "put to work" by all her daughters in helping them with child care and dh doesn't want to continue to burden her and b) because you ARE made to feel like she has done you a favour (I don't feel that particularly, but dh does).
My suspicion is that we will have to start making more use of her once ds starts part time at nursery, because we may need help to get ds back from the nursery to the childminder at 11.30 - an awkward time when you are working full time! My parent are 9 miles away across the city, so it would be majorly inconvenient for them (although they have said that they will help), where MIL is about a mile away. However, dh still doesn't like having to ask for help.
my mum used to say that her FAVOURITE relative (ie even more than her own parents) was her MIL - who was, admittedly, a lovely lady. Unfortunately she died last year at the age of 89. I'm sorry ds won't get a chance to remember her - we were due to go out this year (to South Africa) for her 90th birthday, and he would have been nearly 4, so would possibly have remembered it. Still, we'll be able to tell him he learned to climb stairs at his great granny's when he was 13 months old, when we took him out so that she could meet him