For everyone who is having power window troubles, you need to realize that there are moving parts inside that need maintenance and lubrication. This may take some time to do but you'll be happy with the results. First thing you should do is remove the window regulator and motor from inside the door. Clean it up really good with some kind of cleaner to get all the lubricant-turned-gunk off the gears and plastic window rollers. Clean off the contacts on the window motor so they have a shiney surface and put a thin layer of dielectric grease on them (same goes for the connector inside the door). Apply 12V to the motor and check the motor for noise/slowness. You can also check to see how powerful it is by trying to hold the moving parts together, but be careful or your new nickname will be 'pinky'. Regrease the gears and window rollers with bearing grease (preferably the waterproof kind).
Clean out the track on the bottom of the window really good. It's easiest to remove the window to do this. Regrease the track with bearing grease.
Window switch: Remove it from the door panel and clean the contact posts. Clean the contacts on the connector for the switch also. Clean the inside of the window switch by carefully taking it apart or by spraying it with 'catact/volume cleaner' available at Radio Shack.
Replace the window (without regulator hooked up) and move the window up and down by hand. If there's a good deal of resistance you may need to replace the window felt or simply clean it. If it moves freely then install the motor/regulator and attach it to the window. You should now have a window that operates like new.
Whole process take about an hour to hour and a half depending on how dirty the track and gears are.
