Just a quick(edit: or not) response.
You purchased an UltraBright screen. This is the exactly the same idea as Dell's TrueLife, and Sony's XBrite. All of them have a reflective surface, so before you purchase another laptop, be sure to research that a little bit if the reflections really bothered you. The main difference is that there's a backlight at both the top and the bottom of the screen, rather than only the bottom, like the non UltraBright screens. I've never seen the particular screen you used, but the UltraBright on my m680 is gorgeous, and I get compliments on it from Apple users! (most people say apple notebooks have the nicest screens on the market) It's at least possible you got a bad sample. Again, I don't have your exact laptop, but I do have a 7200rpm hard drive that is mounted right under the right palm rest. I've never felt it get warm at all, even during full disk load activity like a defrag. (again, not saying you're imagining things, just wondering if you got a hastily manufactered model that isn't representative of others) I will completely agree with you that the cases on Gateway notebooks are plastic, and have no real internal strength. The paint is also not durable at all. However, its perfectly possible to configure yourself a $2,500 Dell Inspiron 9300, and I've seen not 1, but 2 of those that don't even sit flat on a desk. HP/Compaq laptops are the only ones I've seen recently that you can disable the touchpad via an easy to access button. Dells certainly don't have a way to, and Gateway doesn't either, as you've found out.
Essentially what I'm saying here is that you've discovered that, just like about 90% of the laptops on the market, a mid-level model that's been heavily upgraded still has some mid-level components. Sure PowerBooks have great keyboards, and super strong cases. The entry level model is almost $2500 if you get the decent warranty and 1GB of ram. I spent almost $3000 on my m680, and believe me, I'm less than enthused about its overall quality. However, at that point, the level of hardware I was getting at that price, in a slim case with a keyboard that has a numeric pad was worth it for me. I'm trying to get a recommendation across to you, if I'd stop rambling. You may want to consider a higher end notebook, to begin with, rather than an upgraded mainstream one. Look at Alienware (though they're owned by Dell now, so we'll see where that goes). Look at some small manufacters, like Sager, or ABS. A friend of mine has an Acer Ferrari that he absolutely loves, and it seems very well built to me.
In general though, now that you've returned the notebook and are somewhat back to square one, consider heavily just waiting a few months. I know how hard that can be, but Merom will be out soon, and if you are really only replace your laptop every 5 years, you really want 64-bit capability. It just makes sense to not put yourself a generation behind, in advance so to speak. The other alternative there is an AMD based notebook of course, which is 64-bit compatible today. Let me reiterate once more, don't take this post as a "you're wrong, i can't believe you said bad things about gateways, blah blah" because that's not what it is. I help lots of people pick out computers and everyone deserves something they're really happy with, especially when they're spending the kind of money you are.