They can be over 6 hours with ideal conditions, which could be all night during the summer at higher latitudes. (On the summer solstice, my city only gets around 5 hours of night + astronomical twilight).
No. "New moon" is just the night side of the moon facing us. A lunar eclipse is when the Earth blocks sunlight from the moon, which can only occur on a full moon approximately every six months.
A new moon is when the moon is between the sun and earth. A full moon is when the moon is behind the earth, and a lunar eclipse is when the earth blocks the sun on the moon during a full moon cycle.