I cannot change aspect ratio

You cannot change aspect ratio when recieving HD signal. Try changing the cable box or satellite box format or aspect ratio.

Keep your Auto Zoom Off set Full screen than only you will get proper picture

You cannot change aspect ratio when recieving HD signal. Try changing the cable box or satellite box format or aspect ratio.

If you are connected to a HD cable or satellite box, the aspect ratio is set by that box. If it is set for 1080i 16:9 wide screen mode then your TV is locked at that ratio. This is good considering you have a Hi-Scan 1080i television in the Sony KP57HW40. Please take a moment to rate my answer. Thanks...

you may want to try changing the aspect ratio on the HD box and the DVD as opposed to the receiver. This should do the thing

As far as I know, you need the cable cards to get HD through the Tivo, because they're what does the HD decoding and output.

That is because you are watching the picture in the 4:3 aspect ratio. This is normal when you are watching a channel that is being broadcast in 480 or digital. But once you tune to a station that has 1080 or at least 720p which is true high def then the picture should expand to 16:9 aspect ratio. It will switch between the two automatically as it determines what type of signal it sees. You can force the resolution to change by pushing the format or aspect ratio button on the remote but you will lose picture quality.

I went into options or menu on LG remote and checked 480i and it worked.

In your philips menu there is an option to turn of your auto aspec ratio to OFF then using your sky remote go to services, 4 then picture and ensure that this is set to 16:9

Job done

Cheers
Little Dish Fitter

Yes, the Tivo will just record in standard definition, instead of high def.

You can still hook the two up together, though.

What I would suggest (and have done in the past) is this:
Split the cable coming out of the cable box.
Hook one up to your HD cable box, and the other up to the Tivo.
Hook the output of your HD cable box to one HD input on your TV
Hook the output of your Tivo up to a different (non-HD) input on your TV.

This will allow you to watch HD while recording standard definition, and vise versa.

Running the HD through the Tivo will work, but will limit you to not be able to watch HD through it.