Toy Story 2: Buzz Lightyear to the Rescue!/The Evil Emperor Zurg

When Zurg appears, run up forward, use the spin attack, lasers will not work on him. Dodge all his yellow and green ion blaster bullets. continue to spin attack him until he gets defeated.

Emperor Zurg Windows XP, 7 PC Speed Glitch
In the PC version of Toy Story 2, there is a Speed Glitch that affects the Emperor Zurg boss battle on level 12. (Keep in mind this applies only for Windows PC version. The Nintendo 64 or Playstation 1 version does not have this speed glitch.)

Problem: Emperor Zurg keeps dodging my spin attack making it nearly impossible to hit him.
Solution: First of all you need all 9 lives and full health to win this battle. Then face Emperor Zurg on Level 12. When you fight Zurg, you need to get Zurg trapped between 2 wall corners so that he doesn't dodge and escape you. Then you have to charge up your spin attack, once it's fully charged, release it and then quickly jump forward at Zurg to hit him and quickly pull back or you will fall down the elevator shaft. Repeat this process and watch out for the yellow ion balls and the homing green ion balls as they will distract and hurt Buzz. Once you drain Emperor Zurgs HPs, he will be defeated and you can continue the game on as normal.