I need to write an iso of windows 7 rc to a partition on my hdd so I can boot it from the hdd. How do I do this?

What you need to do is write the iso to a DVD, and then boot from the DVD-ROM drive to install Win 7.

I dont have a dvd-rom drive

I think you could use this as a template:

http://www.knoppix.net/wiki/Win_Partition

Download an ISO manager such as MagicISO, then create a virtual cdrom drive, mount the WIN7 iso to the virtual drive and start autoplay from within windows, and do an upgrade.

It’s possible to install from a USB drive.

GA, @oratio

I don’t think my computer supports booting through usb (really old)

@jdogg If it is that old, I am not sure you should run windows 7 on it.