OK, wheelchair tips. Firstly, there's a great thread with loads of tips in it listed in the FAQ (I'm afraid I don't have the link to hand, as I'm using my mother's PC). Read that through carefully, as there's a lot of stuff you might not think of. One of the most important is to cover your legs in suncream!
Remember that a wheelchair makes you a lot shorter. WDW is pretty good about this sort of thing, but you will sometimes find that counters are too high. Two ways to solve this: have someone else handle the transaction, or be assertive and make yourself
noticed!
Also be aware that to a lot of people, wheelchair's seem to be invisible. I have honestly had people look directly at me, then walk straight into me anyway! Most of the time it's just amusing

.
When you're renting, try to get one with a proper cushion on it, otherwise she will not be a happy camper by the end of the day!
If you will be leaving it anywhere other than at the loading / unloading area of a ride (i.e. if you're not planning to take it through queues with you), make sure it has something distinctive on it, to make it easier to spot. That said, I would recommend taking it through lines with you, as there's no point her tiring herself out on the queue and not having enough energy to play the rest of the day.
Decorating your chair, even if you don't
have to for identification purposes, can be fun! When we were there in September, I had the wheels all trussed out with various decorations, and got a lot of positive comments. It seems to work as a good ice-breaker and gets you positive attention, rather than negative (plus, as I said, it's
fun!).
I know I have pointed out some negatives, but that's just to prepare you for the tiny minority of jerks in the parks. For every one person who cuts you up, gives you a funny look or does something mean, there will be at least ten who go out of their way to help you - holding a door, offering to carry a tray, picking up something you've dropped etc. etc. etc.! Try to focus on the nice people and forget the jerks - they're ruining they're own holiday by judging other people, but that doesn't mean they have to ruin yours!
Oh yes, that reminds me, doors! There are some doors in Disney that are quite hard to open from a wheelchair. A few methods my fella and I have found are:

Person on foot opens the door whilst the person on wheels propells themself through it

Person in the chair holds out their hands whilst the person on foot pushes them through it (don't go too fast, or you may have some accidents!)

Person pushing backs through the door, pulling the chair and open the door with their behind

Ask a friendly-looking person to hold the door for you
When coming up to a ride, just ask the CM at the entrance where you should go, and they'll sort you out. At Pirates, they will try to convince you to transfer to one of their manual chairs. If you feel happy with that, do so, but be aware that the footplates are stupidly high, which puts extra strain on your legs and ankles. If you want to keep your chair in the line, stand your ground.
Ummm... Well, that's about all I can think of right now. I'm sure you'll work out anything I've forgotten, pretty quickly. Have a great holiday!
