I want to reinstall win 7 without loosing my files, because when windows installed new updates it messed everything up and the computer didnt start showing only blank screen without any beeps, this happened two times which means I cant update windows 7 anymore, maybe there is conflict with the updates somehow which does this to the computer. now I want to reinstall the win7 but dont want to lose anything else or install it twice (win7 and old win7). What option should I chose?
The best options you have could be:
Try boot options like safe mode, go back to a recovery point, i can remember if is still there an option called "last known good configuration".
If this solves your problem, and still you want to re-install windows, back up your files. there's the option to install from the installer on the running windows, it always keep my older files in a folder callerd "windows.old" in "c:" drive, so i can explore this directory later and copy my files back to its original folders, but in a clean windows install.
I think if you do not format the drive, while booting from dvd and try to install above the "unclean" (with the old windows sill on "c:"), you can preserve your old files in the "windows.old" folder too, but this is error prone since yo have at hand the option to format the drive/partition.
if you want to backup, you always can put your disk in another computer and copy, or run from a live-cd linux distro and copy to an external drive, flash, or partition.