From the Premiere Elements Information FAQ http://forums.adobe.com/thread/1042180
•What operating system? This should include specific minor version numbers, like "Mac OSX v10.6.8"---not just "Mac".
•Have you installed any recent program or OS updates? (If not, you should. They fix a lot of problems.)
•What kind(s) of image file(s)? When talking about camera raw files, include the model of camera.
•If you are getting error message(s), what is the full text of the error message(s)?
•What were you doing when the problem occurred?
•What other software are you running?
•Tell us about your computer hardware. How much RAM is installed? How much free space is on your system (C:) drive?
•Has this ever worked before? If so, do you recall any changes you made to Premiere Elements, such as adding Plug-ins, brushes, etc.? Did you make any changes to your system, such as updating hardware, printers or drivers; or installing/uninstalling any programs?
And some other questions...
•What are you editing, and does your video have a red line over it BEFORE you do any work?
•Have you viewed the tutorial links at http://forums.adobe.com/thread/1275830 page?
•Which version of Quicktime do you have installed?
What is your exact brand/model graphics adapter (ATI or nVidia or ???)
What is your exact graphics adapter driver version?
Have you gone to the vendor web site to check for a newer driver?
-If Windows, do NOT rely on Windows Update to have current driver information
-you need to go direct to the vendor web site and check updates for yourself
ATI Driver Autodetect http://support.amd.com/en-us/download/auto-detect-tool
nVidia Driver Downloads http://www.nvidia.com/Download/index.aspx?lang=en-us
You say at the onset that you are using Premiere Elements 10. But, what is your computer operating system and is it using a NVIDIA video card?
How long has this problem been going on? Just tonight? Just this one project? And, have you been creating these projects with this footage successfully for the past several days, past week, past month, or past year?
Have you tried to open a new project and gotten the same problem?
We are not going to get anywhere quickly without more details. The answers to the above will form a base from which to start to ask more pointed questions. But, for now, assuming Premiere Elements 10 on Windows 7, 8, or 8.1 64 bit since you are in a time crunch....
a. What is the word for word error messages that you are getting and precisely when are you getting them?
b. What is your project preset?
c. What are the properties of your source media and how are you importing them into this project....video and audio compression, frame size, frame rate, interlaced or progressive, file extension, pixel aspect ratio?
Does the properties of the source media match the description of the project preset?
Let us start here. I will not be online for about another 1/2 hour. So, if I do not hear from your within that time, I will check in the morning to see what details you have posted.