Dual Core Operation Question

Hey, just a real basic question on how dual core processors work.

When I'm online in Netscape at the UPS website it takes about 30 seconds for a shipping label to process on their servor, come to me and print out on my UPS label printer. During the process I cannot do anything else on my system.....that is, it goes to an "hourglass wait until I'm done curson icon".

If I had a dual core processor system would one of the cores be processing the UPS label while the other one processed any new action I might want to take with the computer? Would I have to have special software to take advantage of the dual cores? Or is that sort of processing already a part of Windows XP?

Thanks for the education!!!!!!
BH