You only need to take a USB cable with you, if you also take your computer.

Rechargable batteries or dock?
The dock offers convenience. It probably comes with rechargable batteries. The dock also serves as a charger. It also powers the camera while you are downloading photos to the computer.

I would get a $10 set of NiMH batteries/charger and make the decision about a dock after I used the camera for a month or two.

Your camera uses a SD (Secure Digital) type of memory card. Your camera may, or may not, have come with one. Even if it did, it probably has a low capacity.

If you did not get a memory card, you should buy one. Get one that is 64 or 128MB. Don't worry about what brand, just buy the cheapest one.

There are card readers available for under $25.
If you know how to use Microsoft Windows Explorer, you will find the card reader to be the best way to download photos to your computer. Windows XP sees the card reader as another hard drive.

Here is an example of a card reader that can read several types of cards:

http://www.compgeeks.com/details.asp?invtid=FPT-D-12&cat=CAM

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