Premiere Elements has its own forum and you'll get better help with video questions there. Moving this for you.
Agreed. We need much more information.
What operating system are you using, how fast is your processor and how much RAM do you have?
What model of camcorder is your video coming from and what format and resolution is it?
When you started your Premiere Elements project, which project settings did you select? If you selected the best project settings for your video you will not see red lines above your clips when you add them to your timeline. Is that the case in your project?