They simply don't compare ;-]
Pentium 4 is way hotter, hungrier for power, less efficient, slower etc.. etc..
it's around 40-60% slower (depends on model) in single threaded apps and 70-90% in multi threaded. It doesn't support 64 bit. All of that doesn't apply for the ones for 775 socket which are more of a core 2 duo than pentium.