If she have an Android phone I would recommend an Android device. It's a no brainer since I'm basing this on thinking that she isn't really a techie person so sticking to what she already own and know is the best solution. I would still recommend Android if someone root the Android for her. After rooting the thing it's straight forward. Just plug and play.
If I'm using it to take notes, I'd get a netbook or something like an eee pad transformer. As I still haven't found a need for a tablet, I must add : I've never used one. lol.
If it's casual use, iPad is the way to go. iOS is mobile computing for dummies- everything is very straightforward. That and the style and marketing of Apple is why it's #1. Also, if you pair an iPad2 with an AppleTV ($99) via Airplay, it's an instant game console and multimedia center. It might all be overkill, especially $$$, but it's good to know your options. The Kindle Fire may be enough for her needs, and at $199, the price is hard to beat. Droid tablets aren't quite as mature as iOS (yet), and cater to a more tech-savvy crowd. Not saying that they aren't as usable, but again, iOS may be better for the 'common' consumer.
The firesale HP Touchpad was my gateway drug into the tablet market, and it's still definitely a toy much more than anything I feel comfortable actually creating content with. Definitely one of the best purchases I've ever made just for cruising around the apartment with, but I'd feel awful if I had to pay full retail for it. Out of all the screens in my life (home PC for gaming/TV, laptop for work/travel, phone for everything else), it definitely feels the most vestigial. There's lots of times where I'll do something on my tablet because it's fun to tap and swipe, when in the back of my mind I know I could be doing it faster and on a bigger screen. With that being said, it IS a lot of fun to use one, and if I were getting one for free, I'd be ecstatic. I would definitely go with the Kindle Fire though for the purposes you listed; while I personally think it's absolutely insane to take notes on a 3.5" screen, if she's ok with it, she'll be fine with a 7" form factor that will be way more portable and way less likely to get stolen if she's pulling it out often in bad neighborhoods. I'd much rather have a Kindle Fire this year, and $300 to spend in the Amazon ecosystem than an iPad, but that's just my feeling.
I have a Fire coming in a few weeks, but for your needs I'm not sure it's the way to go. As of right now we don't know what kind of productivity apps it will have and how well it will work, in terms of documents/spreadsheets/email, etc. It will have 'Android' on it, but it's Amazon's version of it, and AFAIK it will have it's own application store. So out of the box there might not be any access to the full Android Market. I mean, we've been told it will 'have an email client' but no one in the public has actually seen it. We don't know if it'll do anything beyond POP for that matter. TBH, the Fire strikes me as primarily a media content device and that's about it. Which is just fine for what I'm going to use it for. If you can get a Touchpad at the firesale price, it would be worth it, if you pair it with a keyboard or something along those lines and it has it's own basic office suite, but of course with seemingly very little support (if any) going forward there is the risk of it becoming obsolete that much more quickly, and the chances of getting stuff to meet those productivity needs (such as notetaking or other class related apps in the future) even slimmer. Your best bet is either the iPad or Galaxy. More expensive, obviously, but much more support, better selection of apps and they will get all the new stuff that comes down the pipe, particularly the iPad. There are already some notetaking applications available and you will have a better chance of finding cool accessories in the future. Such as these: So, basically...it comes down to how much you want to spend.
Another good thing is that rumor of a Windows 8 might be coming to the Touchpad. This would definitely be the most awesome purchase that I did if true.
Lenovo ThinkPad tablet is what I do most of my mobile computing on. True stylus input and evernote integration made it a no brainer for me. Use this thing for notes, PDF reading, studying, etc. Ipad is great, but its not a true pen and pad replacement like it could and should be.
This rumor makes me want to bang my head against the wall. A 1024x768 display (resolution of the TP) cannot run the Windows 8 Metro UI. Whoever originally reported this rumor (Fox?) obviously did not read or listen to any of the info that came out of Microsoft's recent Windows 8 //Build conference.
As for note taking, she actually does it with the touchscreen keyboard on the iPhone. I figure a separate keyboard could be bought and included but not sure how much use it would get. So if I understand, iPad is now getting the most love simply because she is used to the iPhone and other tablet are for more tech savvy users, right?
I have a Galaxy Tab wifi. (The original not the 10) I enjoy it. Nowhere near Ipad in functionallity, but it has flash and micro sd slot allows for me to put as much content as I wish. I haven't had it very long so I'm just figuring it out. First time with Android too.
Interesting. Perhaps there's a workaround? How old is that thing? I had my hands on one about five years ago and couldn't stand it. If you used a true tablet you would drop-kick the lenovo into the nearest body of water. As for a stylus, I have a capacitive stylus for my tablets that works like a champ. $10 on Amazon.
iPad if she already has the iPhone. Not only will she be familiar with the interface, but her notes, apps, pictures, music etc. will be synced through iCloud.
I usually prefer android but like the others have said, if she has an iphone then get her an ipad. Easy transition for her and yes with icloud it'll be easier to sync her documents. Plus if you use an android phone then you'll have the best of both worlds to switch between with her having Apple products and you having android. At least that's my situation. I have a galaxy tab 10.1 and my gf has an ipad2.