Could a big plane glide significant distances, same a ordinary glider (1000 km or about)?
No, there's no way an airliner can glide 1000km, this is because its wing is designed for fast cruising speeds, and it's much heavier compared to the lift generated than a glider. Gliders are light and have huge wings for their weight, which means they can get lifted by powerful air currents. An airliner is not going to be able to do that. 

The longest glide of an airliner I know of was Air Transat 236, which glided about 98 miles (almost 160km) from cruising altitude to the Azores after it ran out of fuel. The captain was an experience glider pilot. That is really about the limit.

Keep in mind that there's nothing ordinary about 1000km in a glider! 1000km is a very long distance and you'd need a very good glider and a very experienced pilot in just the right conditions.