ahhhhhhhhhhhhhh big hugs...and I'm sorry, no advice to give...experts say that night terrors are not the same as nightmares...so there's really no controllable way of dealing with them (ie// no tv, not too full etc)
I do know that "trying" to wake them can make it worse and that it is liable to pass quicker if left to run its course...
I'm sorry, it is so hard to watch our LO's struggle...I'm praying that it passes for you....my niece suffered from them for about a year between 2.5 and 3.5...my DS is currently avg. one episode every 3 or so nights a week....but his pass very quickly, (my nieces lasted close to 10 mins....)
again big hugs!