What version of Premiere Elements? What computer operating system?
Have you gone through the typical check list type of Q&A
1. Computer optimized...how much installed and available RAM, how much free hard drive space (any supplemental drives like external hard drives), processor and clock speed....run a a free ccleaner program...defragmented computer....scratch disks pointed to location with lots of free hard drive space to accept files that the project automatically generates and stores?
2. What are the properties of the files that you are importing to the project's hard drive? What type of edits are you doing in the project? Are all phases of the program affected with problems - import, edit, and export?
3. Latest version of QuickTime 7 installed on your computer? Video card/graphics card driver version up to date?
4. Problem exists with or without the antivirus and firewalls disabled?
Please give as much information as possible to help us help you.