Windows XP is famous for having very poor control over the hardware resources. If a program requires it, Windows will happily lock up or dedicate plenty of resources to running a specific program. Can be bad programming or some virus/or similar. If she uses Internet Explorer that one is famous for hogging resources like crazy, make her change to Firefox. Run Windows update (update.microsoft.com), then run Windows Error Checking (right click on the hard drive, Properties, Tools), restart and then run defragmentation. Also, make sure to have at least the double size of the RAM empty on the hard drive, to allow for the Windows swap file to use it. You can also always clean out folders like temporary internet files, C:\WINDOWS\Prefetch (all can be deleted!), C:\WINDOWS\Temp (all can be deleted!) and C:\Documents and Settings\USER (go Tools>Folder Options>Show Hidden Files and Flders) and then \Local Settings\Temp (all files can be deleted!) and go to \Local Settings\Application Data and delete the "Iconcache.db" file. Empty the trashcan. Uninstall all programs that she doesn't use!
That should take care of making the computer run a lot faster.
Next step would be to go Run > msconfig > Startup
BE CAREFUL! HERE YOU CAN MESS UP BAD!!!
Uncheck those services that you don't need to start upon startup. Safe to uncheck are services like jusched, qttask, Reader_sl, Adobe_ARM, realsched. Leave all Windows and antivius programs. Search unknown services in Google before unchecking them. Then restart the computer and it will be like new and she'll love you like never before...
