Correcting for what output?
If you have "high resolution" pictures and you are creating a DVD, you are limited to the 720x480 resolution of a DVD... as it says in this FAQ article http://forums.adobe.com/thread/1187937
Otherwise, more details are needed for someone to help you
What is the situation - I do not really see the typical 720 x 480 resolution vs HD resolution type of question. I am seeing it as a photo editing (sharpening) question which may or may not be related to further use of these photos in Premiere Elements 11.
Which of the following is applicable to your situation..
a. You have great looking photos saved on the computer hard drive, but, after you import them into Premiere Elements, they look blurry on the Timeline and you want to try to correct that
b. You have great looking photos, but, after you import them into Premiere Elements and burn them to DVD-VIDEO on DVD disc, the photos are blurry in the playback of the DVD-VIDEO with your TV's DV player
c. None of the above, rather you are trying to improve the sharpness of your photos in general using Photoshop Elements Full Editor/Filter Menu/Other/High Pass. If so, have you tried the Unsharp Mask under the Enhance Menu?
Consider the distinction between sharpening an image (contrast changes) and trying to correct a bad blur in the original.
From all that you have written, I suspect that this involves "c" and how to get the best results for sharpening an image in Photoshop Elements. If that is the case, you might seek input from the Photoshop Elements Forum here on that. Another possibility is that you may be creating pixelation in your images if you are up-sizing your images in the search for higher resolution and better quality.
Please give as much more detail to make sure that your question and its answer can be targeted correctly.
Please do not forget the follow up which is the key to success.
It looks like there was a problem in posting your reply to my questions. I do not see any message in the reply field of post #3.
We are looking forward to your progress, so could you try again to post your message.