It appears that Jasc PSP 7 is over ten years old? The version you have is probably not compatible with Windows Vista or Windows 7, which is probably why you cannot use it properly.
http://www.winplanet.com/article/1559-.htm
As Corel purchased the rights to PSP from Jasc in 2004, you'll need to contact Corel for help, or for a Windows 7 compatible version.
Good luck.