As a DM, I have ruled that spells with the range of
Touch are the only spells that allow you to use the holding
the charge rule from Chapter 10 of the Players Handbook.
My players argued that any spell that uses a ranged touch
attack, such as disintegrate, also qualified. Which is correct?
Look at the spell's range entry. If it doesn't say touch you
can't hold the charge. Disintegrate is a medium range spell
(100 ft + 10 ft. per caster level), not a touch range spell. Because disintegrate is a ray, you do indeed make a ranged
touch attack when using the spell, but that's not the same as a
range of touch.