I have a idea. this is not losing files
You can go and buy or borrow a hard disk box fit for you disk drive of the old one.the hard disk box can enable you to access to hard disk drive by usb,and use the old hard disk dirve just like a "big" flash disk.
oh, I got another way .
I call this Plan B,the previous it PLAN A.
you can borrow a install disk of windows XP or win2k ,
use the disk to install system,before the setup program copy file to hard disk,you should choose another logical drive (not any one of your systems install on your current system, I assume that you might install more than one system on your computer) .After rightly installing the new system,you can copy files or any other thing your want .If you can't intall the system try PLAN A !
good luck,buddy.