There are a couple of things you can try...
(this one goes without saying: make sure your system meets the minimum requirements to run PS)

1.Install the latest "service packs"

2. try running PS alone

3. Recreate the "pref" file in PS (search for Prefs.psp and rename, then launch PS)

4. Verify your device drivers are compatable with XP (sometimes a scanner/TWAIN driver can crap out on you and kill the launch)

5. Check and change (if needed) the virtual memory paging file.

6. Check your fonts (because PS loads a font list at launch it can crap out there to).

try to watch the splash screen as PS launches and see where it dies on you, than post back here.

:)
good luck,
RetroCity