Does BG2 use the same engine as PS:T?
If so I assume it will look similar and can be modded with the widescreen mod?

They use the Infinity Engine.

From the blurb on Gibberlings 3 :

"The Widescreen Mod allows Planescape:Torment, Baldur's Gate: Tales of the sword Coast, Baldur's Gate II: Shadows of Amn, Baldur's Gate II: Throne of Bhaal, Icewind Dale: Heart of Winter and Icewind Dale II to be played at previously unsupported resolutions, like those of widescreen monitors."

Thanks