The best - Shadowprotect Desktop Edition
http://www.storagecraft.com/shadow_protect_desktop.php
I always use their Vista PE based recovery disk to backup and restore my Windows XP and Windows 7 machines. Have not experienced any problems. Even today I restored my XP machine using Shadowprotect Recovery CD. (backup stored in an external drive)
I jettisoned Acronis True Image long back since there were reports that they modify the MBR almost irreversibly making it impossible to try other backup software.
Since then I do not install any backup software on the machine. I always use the bootable recovery CD which kicks in the program to make the backup images and also to restore.