i'll assume you're NOT using the iTMS, as you're in venezuela. Legally, you must remove all MP3 or AAC music files, they're going to be illegal if you give copies away. But as long as they're not protected AAC (if you ripped them, they're not protected), it's technically possible to leave them on a computer and copy them to the new one, either by HD or iPod hack... i would load the songs onto the new computer before deleting the old ones, if i were you, just in case your iPod chooses that moment to die...
but, ahem, you have all of the CDs, so you could just re-rip them to the new one 😉
pnw