A few questions about netbooks.

I want to get a netbook. I want something that I can use for downloading through the night because my main pc is noisy and uses a lot of power. Also like the idea or being able to carry it around.

Would downloading every night ruin the 2.5" hard drive or are just the same as 3.5". Or should I save to usb, external hd or memory card?

Also do eee pc's run of the mains if you remove the battery. Don't want to wear out the battery.

Oh one more thing. can you play video on a 23" and 37" tv with the vga port? or would it struggle?