Isuzu Bighorn gear issues.

Sorry i'm just a horsey girl so please excuse my car "language" haha.
I tried to drive home in the snow today.had it in 4wd and in drive on the icy road, it was revving quite high but was ok, when i hit the main road, the road had been cleared so tried to take it out of 4wd.no go, couldn't get it out, so tried to carry on in 4wd, it wouldn't go above 30ks without revving really high and not really goinbg forward normally.i pushed 4wd lever again and it jumped out with a grinding noise.then wouldn't go forward at all in drive, then when i panicked and put it back to park it made the most awful grinding, crunching thunking noise.promptly rang tow truck, who suggested i put it into 2H which i did and it goes forward but again at high revs anything above 20ks, so got him to tow it home, and was told to try it again, and the same deal, except now the 4wd lever is in nuetral, but thinks it's in 4wd.same horrible noise when gears being moved from drive to park.am i looking at something HUGE!
Thanks

Bump.any advice.a bit of car knowledge.

OK, sounds like in the beginning you had it on "low range" 4wd. You have tried to to both select 2wd while moving and when that failed jammed the auto trans in park while moving. Not a good thing to do.
Start from scratch, go start your vehicle. Put the trans in neutral. Then shift the transfer case into 2wd. You may have to go into drive and reverse and roll a few meters to unlock the hubs and ease the load on the transfer case. You vehicle may be push button 4x4, ie, you push a button to engage 4x4. If that's the case, put the big lever (auto lever) in neutral, the little lever (transfer case) in high and press the 4x4 button to disengage the 4x4. Again you may need to slowly roll forward and back to unlock everything.

cant fully remember with the Bighorn but if I remember right you pull back from 2h into 4h them towards the right and forward for 4l. You may have put the lever back forward into 4l rather than 2l

You can't change from L4 to H2 while you're driving. The vehicle has to be stationary. Like 'berg' said, the main gear lever must be in neutral before you shift the 4WD lever.

how did you get on ,did you sort it out