Quick Newbie Help Please - Canon EF-S 55-250mm f/4-5.6 IS II

Hi all,

I need help with something. I'm a total newbie to dslr and don't really understand the lenses yet. I was reading about the differences between the Canon EF-S 55-250mm f/4-5.6 IS II, and the Canon EF 70-300mm f/4-5.6 IS USM Autofocus, and a reviewer on one website said something about their not being focus or zoom "inside the lens" on the 55-250mm compared to the 70-300mm.

Can someone explain? What's the difference between the two lenses?

Also, if someone can answer, will the EF-S 55-250mm f/4-5.6 IS II autofocus if I would use remote live view on my PC to control the camera? Will the 70-300mm wok better for this?

I have physical challenges and need to tether the camera to my pc, put it outside, and take photos of birds using the live view software.

Thank you!