Couple of things to look for:
1) Will the window go down, and when it goes up, sticks to that one position?
2) Is the window edge even from left to right?
This is a common issue with H1's until 2001/2002. If you are able to get the window down, take some silicone spray lube and spray the inside of the tracks liberally using the small red tube.
If your window is cockeyed from left to right (one side higher than the other), take the heel of your hand and gently get the higher end even with the lower end. The window will then unbind. Follow the fix for #1.
If the window does not go down at all, your window regulator may have seized.
To replace and look at the power window regulator, take a gander at the AM General Body Service Manual page here:
http://www.azhog.org/amg_manual/amg/...RVICE/8S10.PDF
Go to page 10-39. The manual shown is for the 1998 model year, but there is no difference in parts between 1998 and 2000 in regards to the door components.
Hope this helps,
Steve