Yes, the Nintendo 3DS can connect with the NDS lite, only if the game is compatible for both devices.
3DS games cannot be played on a DS lite. You need a console from the 3DS family - 3DS, 3DS XL, 2DS, New 3DS, New 3DS XL.
Yes the 3DS and DS lite are the same size
The DS lite is almost exactly the same size as the 3DS.
No, the Nintendo DS lite cannot play 3DS games.
About the same as the DS Lite
actually nintendo has no plans for making a nintendo 3ds.
Yes, the Nintendo 3DS (as well as the 3DS XL and 2dS) has its own 3DS games that will not work for the Nintendo DS, Nintendo DS Lite, Nintendo DSi, and Nintendo DSi XL.
Nintendo ds lite-2006 Nintendo dsi-2009 Nintendo 3ds-2011
No the 3DS game cards are shaped slightly different then the Nintendo Ds. Of course if you could put the 3DS game cards in the Ds lite it would still not work because the features and intense graphics the nintendo 3DS requires for games can't be used on the Ds lite. Don't buy 3DS games for the Ds lite as it just won't work. You can consider buying a 3DS however as the 3DS is backwards compatible with all DS games.