PDA for Nursing Student

Hi there,
I've read a lot of these threads and have gotten a lot of good info. I have a couple of things I still am unsure about.

1. Are there any non-phone PDA's still being built/used out there?
2. Is the Palm TX compatible with Windows Vista OS? (Saw one quick blurb that it might not be...)
3. Are there any phone-PDA's that are better than others and don't have a camera?
4. Is it mostly the camera feature that some clinical sites won't allow, or is it the phone as well?
5. If I go with a phone, is screen size an important factor?
6. Also if I go with a phone, do I have to set it up as a phone to use it, or can I just use it as a PDA and not have the phone service?

Thanks in advance for the help!
Ken!