Well, I kept it simple and this is what i did to achieve this.
a) Copied the entire content of the RHEL distro that i downloaded to a folder in my system. Lets say D:\rhel4as
b) Then downloaded the "mkisofs" & "cdrecord" for windows from this link:
http://smithii.com/cdrtools
c) Then gave the following command to create an ISO image that if we burn will make the DVD bootable.You have to give this command when you enter into the directory that you have copied
c:\rhel4as>mkisofs -o rhel4as.iso -b isolinux/isolinux.bin -no-emul-boot -boot-i
nfo-table -joliet-long -publisher RHEL -r -V RHEL4AS -graft-points /rhel4as
Make sure you have the ISOLINUX folder there (which it should be from the default DVD)
Cheers !!