i dont think that either of us can say what the O.P. needs or wants. He asked for opinions and i gave him mine and you gave him yours, and what he does with that advice is up to him now.
In my post i said that in my day to day tasks. there is no difference between each. and i'm sure my day to day tasks are similiar to anyone elses. web, music....maby a movie. msn now and then... if i was basing my opinion on my own usage i would have to emphatically say that the dual is practically useless. But i'm anything BUT an average computer user. i would go so far as to say that my computer usage is quite extreme, and that the quad is such a boon that i really cannot comprehend how anyone wouldnt think so. That being said, i can honestly say that there are of uses for a quad outside of gaming, none of them spectacular, usually quite mundane, but not something you would normally think of using if you didnt have a quad to try it out with.
now i'll say again, that for every day things the dual an the quad make no difference, anyone would be just as happy with a dual over a quad if they knew no better, and alot of people dont. but the quad being practically the same price as a dual will give you options, and cost you nothing in performance, and very little in money. and that is all my point is about.