I need to upgrade GPT partition system from MBR while reinstalling windows. But it would erase all the data from the disk.Help

[idkwhattodo]

Hello guys, My windows is corrupt. I need the data in the E and D drive. But i can't back it up given my windows does not even login.
So i tried reinstalling my windows but after entering the key in the hard disk partition it shows that i need to
"windows cannot be installed to this disk. the select disk has an MBR partition table. ON EFI systems windows can only be installed to GPT disks" -

http://www.disk-partition.com/articles/images/mbr-partition-table-to-gpt/mbr-partition-table-to-gpt.gif

This is not from my computer but from google search. Just want to let you guys know the error.

I need to format my harddisk to gpt but in that process i will lose all the data in E and D drive. I don't know what to do. I can't afford to lose that data.

Is there any way around. I read online MBR is an older partition technique and GPT is newer one. Every solution i found stated that i need to format my hard disk but i CANT afford to lose the data.
Just so you guys know all the details, this is a laptop of lenovo and not a computer rig.

EDIT: I also read online that windows 8 needs GPT partition i had windows 8 installed before and now it is corrupt. Would installing windows 7 be the solution?

Help would be much appreciated guys. Thanks for reading.

 

[kanewolf]

If it was me, I would spend $50 on a 120GB SSD, install the OS on the SSD then connect your existing data drive.

 

[idkwhattodo]

If it was me, I would spend $50 on a 120GB SSD, install the OS on the SSD then connect your existing data drive.

but i don't think my laptop has space for ssd. Also that it is pretty old.