You should visit the Microsoft's website and check for the system requirements. If you are close to the minimum system requirements specified there, it's time to upgrade the system or consider a lower version of the OS, whichever you could afford. I would suggest the former.
Okay, when you get the computer to work, try and free up as much space as you can. Try to see if some of the LARGER pictures are taking up too much space (and then resize them) with Microsoft Photo Editor (if you need help with this then PM me).
Try to make sure that you don't have so many things running on startup. Windows XP can be a resource hog.
I believe there is some way around this. I will look into your problem tomorrow and see what other possibilities exist. (I'm a little short on time at 12:34 am) sorry lol. Keep checking this website (this thread specifically) for updates.