CPU - which of these is better

If I had two cpu hungry applications and a couple of lesser hungry ones (running on win 2003), which of these would be better?

1.) Intel Pentium IV 3.4GHz (1MB L2, 800MHz FSB) with hyperthreading
2.) Dual Core Xeon 3040 - 1.86 GHz - 1 x 2MB cache

I dont really understand hyperthreading and cache’s so :stuck_out_tongue:
cheers