Well, unless you have an unlimited budget, I think you would be better off deciding how much you are willing to spend on a laptop, then work backwards to decide what kinds of machines are available within your price range. There's no point in doing a lot of analysis to determine that your optimal machine would cost, say, $2800, if you can only afford $2000 (or whatever). I'd suggest doing some research based on price to whittle down the set of choices, and along those lines I'd also suggest considering buying a used laptop. For a given dollar amount, you may be able to find a top of the line (but used) 2003 laptop going for the same price as a low or midrange new 2004 laptop. Check the specs.
Regarding your specific questions, my 2 cents are:
1. Doesn't matter, but the overwhelming majority of laptops use Pentiums. I've used AMD's and Intel, and they both work just fine.
2. It depends. How much can you afford? Faster = better, but how much you really truly "need" is a subjective call. I'd say as long as it's over 1G, you'll be fine.
3. It depends. How much can you afford? More = better. I'd say at least 256Mg.
4. Ehhh, wrong question. You are really asking 2 questions: Q1. "How can I be sure I am getting the maximum performance out of my machine?" A1: Just be sure you have a reasonably fast CPU and reasonably large RAM. Manufacturers simply don't make laptops with seriously unbalanced components (meaning either superfast chips but puny RAM or vice versa) so pretty much anything you pick should be fine. Note also that many laptops allow you to add more RAM as an option. Q2: "All I really want to do is buy a laptop that I'll love so much that my friends will constantly need to tell me to shut up about it -- how can I be sure I'm buying the right one?" A2: When it comes to laptops, there are only 2 things that matter: a. Battery Life b. Everything Else. Believe me, given a choice between a plain Jane laptop that can last for 5 hours vs. a flashy rock star laptop that dies in 2 hours, smart people will pick the plain Jane model *every single time*. Consider it this way - have you ever had a cellphone die in the middle of an important call? Having your laptop die in the middle of an important work assignment is 10 times worse. Again, just my 2 cents but think about it.
That being said, here's my ideal laptop (after removing the preinstalled OS, of course): http://www.newegg.com/app/viewProduc...146-013&DEPA=0
Good luck with the decision. -- J.W.