Photoshop Elements 9 installed on two computers. Now one of them fails to launch.

I have Photoshop Elements 9 installed on two computers, a desktop and a  laptop. The installation DVD came as bundled software with a Wacom Pen tablet. I was recently using PE9 on my laptop, while drawing software was active in the background, and I believe may have produced some conflict between.

Since then I have been unable to open up either of the programs. One thing at a time. As PE 9 has already been installed on two machines, how do I stand with uninstalling and reinstalling it on my laptop.  This would not be a case of installing PE 9 on a third computer.