In reply to The Lemming:
The normal way to do this is to recover the files to somewhere else - your computer for instance. Once you have done this and check everything you want is there then you can wipe the SDcard (reformat it whatever) and then you can put back the files you want.
Testdisk etc will try to prevent the computer from writing anything to the original card because this risks damaging the filesystem it is recovering- it may have marked the card read-only or remounted the card read only.
Copy your data to a safe place, but before you do make sure the files are what you think they are - not just files with the correct names - eg check the photos do actually contain images. Check the files with odd names aren't something you want to keep (but with the filename bollocksed up).
It's generally a good idea to be sure you have everything you want before you clear than restore the card and keep this copy for a while after you put the data back just in case you forgot something.
Good luck!
Post edited at 23:01