My favorite live CD is SystemRescueCd http://www.sysresccd.org.  This includes Petter Nordahl-Hagen’s chntpw. It also includes gparted, partimage, ntfs-3g file system (safe, reliable, writable ntfs), clam antivirus.  It auto-detects many kinds of hardware and even connects to WPA access points.  You can put it on a small USB drive and create a backing store, so that it retains changes made.  You can even install additional packages and customize it.  It also contains boot images of several other programs, like dban, freedos, memtest+, aida hardware analysis and diagnostic tool.  You can also add additional applications to SystemRescueCd that aren't included by default, so I added spinrite to my copy.