Change Laptop for PDA, iPAQ 1940 or Acer n30

Hello. Last time I think about purchase palmtop with PocketPC - It will be my first PDA. I like when I can write text, recieve e-mail and watch movie for example on holiday - At this time I use laptop PentiumII + Nokia 6210. I'm fed up carrying 2,5 kg laptop so I want replace it for some good PDA. That's why I have few questions:
- Have you got similar experience with handheld devices and laptops, can PDA replace laptop in this tasks?
- I read few articles and I think that the best choice for me is HP iPAQ 1940 and Acer n30 because both of them have bluetooth but I think about COMPAQ 3870 too. Is there alternative for these PDA?
- I need some mobile phone with Bluetooth and GPRS. I think about SonyEricsson T68i. Are there other cheap mobiles with BT i GPRS?
- Has 1940, n30 i 3870 got built-in backup battery? I can't find information about it.

(Sorry for my English - If you see serious miastakes in my post - I'll be glad if you tell me about it michal.tuleja@plusnet.pl ;-))
Thanks
Michal