hey i just did a dual boot on my second rig (dell dimension 2400, P4 2.6Ghz 512 DDR 333) to try to familiarize myself with Linux. and i ordered a 64 bit version of Ubuntu from their website to do a triple boot on my main rig (see specs <-------) is there a performance dif between the 2? i have never used Linux before so i know nothing about it, but so far i am liking it. also any tips for customizations and or tweaks would be appreciated. thanks.