Hiren is your friend here. http://www.hirensbootcd.net/ For all your diagnostic and boot needs.
Follow the instructions on the following URL & it should sort you out.http://www.howtogeek.com/howto/windows-vista/how-to-make-a-windows-vista-repair-disk-if-you-dont-have-one/ or go straight to this one.http://www.neosmart.net/blog/2008/download-windows-vista-x64-recovery-disc/ I know when you follow the download link it says "Windows Vista x64 recovery disk" but if you scroll down just a little you will find it has versions for both 32 bit & 64 bit Vista and Windows 7. Hope that helps. Kev.
have you seen this yet? http://www.ubcd4win.com/ you need a working installation to build the disk, so it's important to do it now, rather when your PC is broken. see this question in the FAQ: http://www.ubcd4win.com/faq.htm#vista