Window issues 2002 xterra 4x4 se All windows are slow to go up and down (electric) but the driver's front will not go up without pulling on the rear corner. I removed the door panel but nothing stood out except the rubber in the window guide is cracked and no longer sits flush. I'm heading to the dealer to ask for suggestions but feel I'll be told to simply buy a new motor and or regulator.

SOURCE: electric window motors

They should be the Same Motors.

SOURCE: 2002 Nissan Xterra drivers power window wont roll down

Quite possibly yes...I would first check any relays and/or fuses just in case.  A few dollars for a fuse or relay is much cheeper than say $100.00 and a few hours of labor.  
You can purchase just the window motors from any major auto parts stores.  You can also purchase the window motor with the regulator.  The regulator is kind of like a rope and pulley system to lift the window up and down and the motor is attached to this assembly.  It is a little more expensive but I would change both.  I always change both just in case the regulator is bad and it isn't the motor.  You will have to remove the plastic interior of the door in order to change either the motor or the motor/regulator assembly.

Any questions, feel free to ask!

SOURCE: LF Window will go down but will not go back up.

replace switch

SOURCE: how to remove front door panel on a 2002 nissan

http://www.youtube.com/watch?v=Te-Oetp-Omw