I think the laptop/station is the better option. In fact, I wouldn't even suggest the laptop/desktop combo. As UVAMalex pointed out, the issue of space is important, as being in a first year dorm room (old or new dorms) is cramped enough without the troubles of an extra computer floating around. Most likely, one computer will be used far less than the other, which brings up the cost issue. Why buy an extra computer to rarely use it when you can buy all of the components you want for less? You can buy a 19" LCD for $100 these days (not Sony or something, but I got a really nice one that I love from Costco for $115), wireless keyboard and optical mouse for $40, and the docking station will be ~$100-200 depending on the brand. IMO, that deal is so much better, especially since laptops are getting so darn cheap and performance is going through the roof.
Now, onward to your second question. The notetaking software would work with a tablet computer, which I own. Virginia Tech (where I am currently, but transferring to UVA in the fall) required them for my class, realized it was a dumb idea, and now is going back to plain laptops. I have a Fijitsu Lifebook T4200 (now 4215,
http://store.shopfujitsu.com/fpc/Eco...o?series=T4215) and love it. It's a tablet PC, and Fijitsu makes the best tablets that you can find, hands down. Toshiba, Gateway, and HP all make models too, and I knew people who had the other brands but always had either issues with them or wished they had gotten a Fijitsu. When I bought mine, I spent about $3400 for the computer, warrenty, and such. Now, the most expensive model with all the bells and whistles (100GB storage, 2GHz processor, ect) is $2100, probably around $2400 with the extra 3-yr warrenty. They keep getting cheaper and cheaper as well, and perform just as well as a "regular" notebook laptop. With the tablets, you can convert it to the tablet mode and write on it just as you would a notebook, which eliminates the need for notebooks and pens and pencils and other junk, which I love. I took it to every class and typed when I wanted to and wrote when i wanted to. My life was in that computer. If your daughter wants to further look into a tablet, PM me and I'll help give you some first hand opinions. When I first got it, I thought I would hate it and never get used to it. Now, I wouldn't trade it for anything. It's coming to UVA with me and I'm happy about that.
On a side note, the thing that I love the most is the fact that it's a 12" screen. Yes, it's small. But the point of a laptop is for it to be small and convienent. IMO, the huge things my friends lug around are not either of those two things. And since your D is already thinking about the docking station route, I would highly suggest going for a 15" or even 12" screen so its small, lightweight, and portable, and have the docking station/17" or 19" moniter/keyboard/mouse set-up, and do her term papers on that set-up when she would like a big screen to see everything. I got used to my smaller screen really quickly, and most people do. I doubt I'd go back to a bigger screen, it's just pointless. As for the CD drive, its a hassle to have it external. Minimize the screen, not the hardware. Also, look for computers that have removable internal CD drives. Mine simply pops out and I can replace it either with a spare battery for more battery life or I can put in a plastic "protector" that weighs almost nothing, so it reduces the carrying weight if i'm going somewhere and know that I don't need my CD drive.