Corrupted memory card??

On holiday at Disney I used a flash card (HP 32 GB Model sd200) for taking photos and videos which I then put onto the Ipad and uploaded to our external hard drive (Seagate Backup Plus) which was connected to the router at home. Once home I connected the external hard drive to laptop (Toshiba Satellite e55-A Windows 8) to download the photos. But as I connected the hard drive a message appeared saying there was a problem with some files. I downloaded what I could, but not all the photos appeared to be there (2 days worth were missing). I have then tried to recover the files from the memory card (I had already deleted the photos to use the card again for the next few days of the holiday as I had thought they were uploaded to the external hard drive at home). I used Recuva, this found two files with the correct dates for the missing files but the files were recovered as .DAT files not JPegs. I cannot seem to find anything to open these files that shows me the photos. I tried downloading FreeFileViewer but this does not open them as photos just as list of numbers. As you can imagine two days worth of photos of my 4 year old at Disney is not something I want to lose I would appreciate an advice.