1. Who is Stryder?? What does he look like and what's his race??
Stryder is Aragorn. He looks like Aragorn. He's human.
2. When Frodo was looking into the water in the swampland area, what were those ghostly figures in the water?? And what did they represent??
Those were the drowned men and orcs who fought on those swamplands and lost their way in times before.
3. The Ents were upset because some of their friends were chopped down and used for a fire........ Was this done earlier in the movie by the orcs when they were camping out??
The orcs and Saruman chopped them all down in FotR to power their forges below Orthanc.
4. Frodo and Frodo's chubby sidekick were captured by this band of warriors, because the guy's brother died and he thought that Frodo did it...........But what I don't understand was, What was he going to do with Frodo?? And who was he being attacked by near the end of the movie??
That was Faramir, brother to Boromir. When he found out he had captured the Ringbearer, he was originally going to (in the movie, not the book) take him and the ring back to help defeat Sauron's forces. They were being attacked by the orc and men forces who were fighting for Sauron and Saruman.
[ 08 January 2003: Message edited by: Baron ]