Is it possible to install windows without losing any files / data

[YoungDNL]

So i recently recieved a black screen with a white underscore flashing meaning the OS has messed up somewhere, I was thinking if I could get a new OS without losing files on the hard drive. I have 3 Hard drives, 320GB which the windows is on and 2x 500GB which is documents, games, files and etc. Is it the possible to get a brand new windows ( Currently i have windows 7 home premium ) like a windows 8.1 or 7 Ultimate without losing files? and if i keep my files on 2x 500GB will it stay there as normal once plugged back in? If there is something else i should do what would you recommend me to do?
Any additional info needed, please ask

 

[DSzymborski]

A clean wipe ought to only cost you the files on the install OS. Best to keep the other hard drives disconnect while you do a full, fresh install on the OS drive.

Though more troubling is the worry about losing files. That suggests to me that you don't have a backup plan. If you have files that aren't backed up elsewhere, the only question is when you'll lose those files, not if. If this is accurate, it's something you need to remedy quickly; regular backups of important data are just as basic a part of PC ownership as changing the oil is for car owners and changing the air filter for furnace/central air owners.

 

[YoungDNL]

A clean wipe ought to only cost you the files on the install OS. Best to keep the other hard drives disconnect while you do a full, fresh install on the OS drive.

Though more troubling is the worry about losing files. That suggests to me that you don't have a backup plan. If you have files that aren't backed up elsewhere, the only question is when you'll lose those files, not if. If this is accurate, it's something you need to remedy quickly; regular backups of important data are just as basic a part of PC ownership as changing the oil is for car owners and changing the air filter for furnace/central air owners.

Yeah I didn't do a backup, i do have a spare usb hard drive is it possible to back the files up?