Lost Pictures/System Restore

Hello,
My husband hit F10 on our HP. This caused the system to delete all of our pricutres, , documents, saved files, etc. Is it possible to get any of these back??? A friend of mine works on computers and had a few programs available to run to see if any of the pciutres could be retrieved. After he did a system restore, he was able to recover some but not all of the pictures! It looks like all of the pictures are still there (in files), but they cannot be opened/viewed! Some of the messages I receive when trying to open the picutres are:

Windows cannot open this file: choose a program to open it.
It opens in Microsoft Picture Viewer and says 'no preview available'

A bunch of pictures were downloaded and saved on the same day, but I can only view some of them! There are some really old ones that I can view and some newer ones, but there are some in between that cannot be viewed!

I don't care about anything but the pictures! Is there a way to retrieve these...any programs I can buy or places I can take it in to?

Any suggestions or comments would help! Thank you!