Hi there,
I am currently running Windows 7 32 bit, and I am trying to install 64 bit. My problem lies in that when I try to boot from CD, I get the message Loading OS, boot from CD... where it will stay even when I have inserted my disk. I believe it is probably the CD, but if it is caused by trying to install it when 32 bit is already present and I need to re-format my hard drive or something like that then I would greatly appreciate if you could let me know.
You would need to format and re-install fresh. As far as I am aware it's not possible to "upgrade from 32 bit to 64bit".
You should however be able to insert the disc, reboot and boot from the disk rather than the harddrive. Then follow the on screen wizard to format your HDD and re-install windows.