How to recover files from a partition that was previosuly NTFS under Wndows but after Ubuntu installation had been converted to ext4?

I had accidentally installed Ubuntu 13.04 on Windows 8 while trying to Dual Boot. I had a single partition(973GB) which had windows with NTFS filesystem. But by the accidental install of ubuntu the filesystem had changed to ext4.

When I tried testdisk, it showed me three partitions:

1. P EFI System (with very less data)




2. P MS DATA (the large disk of around 950GB. I think this partition has all the data)




3. P Linux Swap (same size as my ram)

Now when I tried searching, it showed that the partition MS Data cannot be recovered. I dont need the partition or the windows 8 back. I only need some of my important files that got deleted. Can I recover these files? Please help.