It really depend what you want to do so a few assumptions I think.
Given you are running XP, the Windows viewer that is part of the OS is perfectly fine for viewing photos. If you want a programme that can help resolve red eye, brightness, contrast, then there are loads and its just a matter of choice, I use Microsoft Picture it 9.
If you want to turn your photos into a slide show with background music and then burn to Cd for playing on your DVD player and main telly, again there are lots of choices, again for me Photo to VCD from Wondershare is great. Hope this helps post back if you want more.