How do I install a new hard drive and a mirror image of the OS,  MS Office, and other programs from the old hard drive?

My Husband, Mom and Dad cannot function using Windows VISTA.  What's even worse for them is Microsoft Office 2007 which looks and feels so so different from MS Office 2002 and 2003.  So while my boys and I will upgrade to VISTA and MS Office 2007, I need to keep Windows XP and MS Office 2002 going on at least the 3 oldest computers (DELL 4550, 8200, and XPS 700) for the "traditionalist" in the family.  These 3 computers are all old and the hard drives need replacing&one just died!   Once I buy new hard drives, how can I transfer (image?) everything (including OS and MS programs) from the old drives to the new drives (like a mirror image)?    I am not sure if I should use  Acronis True Image or Casper XP or Drive2Drive or What?  I have various DELL install discs but unfortunately I dont know which goes with which computer and the same goes for the MS OFFICE discs so I need to copy everything as a true image (registries, boot files, and all) of the old drive.   The second part of my question is what program should I use to create and maintain a mirror image of my master drive once I install a new second drive in my DELL XPS 700 which is running Win XP?  I want the 2 drives to be mirror images in case one fails (ie RAID 1).  If I use a RAID 1 configuration do the 2 hard drives need to be the same size?  In other words, if the second newer  HD is bigger than the first Master drive is that a problem? Appreciate your advice.