That's unfortunate. Everything I've heard about the D-series Latitudes is that this is a fluke, but I'll admit to having used relatively few 600s and 610s over the years. The 620s and the 630s that have integrated graphics are completely rock solid. (The 630s with discrete graphics have the nVidia graphics with the bad soldering -- not bad machines, but they'll potentially need to be repaired in their lifetimes.)
The E-series is also solid, from everything I've heard.
This all presumes the barest modicum of respect for the machine, of course. Any laptop is going to have its power connector fall off the board if you exert enough pressure on the power connector, and any laptop is going to develop issues if you put it on a carpet and never clean dust and fibers out of its ventilation ducting, and any laptop is going to develop a bad disk if you drop it on the floor enough times.
Yeah, I usually would keep the D610s on my bedside table, and I treated them fairly well. I would usually carry them around in my backpack at the very back behind all my books. If memory serves I actually got both laptops with the issues present already. With the charger issue I could usually just stick a book or a Gameboy or something under the tip of the power cable and it would charge, but it stopped working after a few months. As for the one with the power button issue, you would have to apply so much pressure to it to get it to turn on, and as such I rarely ever turned it off. By the time I gave up on it the power button (The inner part, the physical button fell off ages beforehand) had become so scarred and marked up from where I kept stabbing it with a pen to get it to turn on that I was surprised it hasn't cracked in half. (I would have to use both hands to apply enough pressure.)
I'd consider another D610 if I could find one in decently cared for condition, I really do like the feel of the laptop (just big enough, just heavy enough, not to little, not too much) but I'm looking for something with at leas a core duo and a decent graphics card.
Without considering software at all, my recommendation is almost always a Latitude or a ThinkPad -- they're more flexible systems in terms of expansion and options, they're often available for less than a Mac notebook, especially if you're looking at used/refurbished/off-lease machines such as from geeks.com or dfsdirectsales, and there's often a way to get a better LCD panel, not to mention nice little things like the epic ThinkPad keyboards or the ThinkLight, which I still prefer over a backlit keyboard any day of the week.
But if Mac OS X is a top priority for you, then buy a MacBook, but be aware that you're comparing a budget-conscious consumer laptop (with relatively well-documented issues with its casing) to the top tier of corporate fleet laptops, often with no known defects or weaknesses, just depending on the model and vendor you go with.
Another option if you're just looking for something to run modern apps is to get a desktop -- if you're not taking a bunch of in-person classes or roaming around the world with your computer, a desktop is almost always going to be cheaper, faster, more durable, longer-lasting, and easier to repair if something does go wrong. Even I'm guilty of not giving the desktop quite enough credit, in this modern world of going to a cafe and using somebody else's horrible Internet connection, or taking your laptop to the sofa.
Yeah, personally I'm leaning toward ThinkPad. My budget is about $250. As for Mac OS, the funny thing is it's not that at all, honestly looking over the specs of comparably priced laptops, I really can't justify buying a MacBook to myself anymore, but there's still something there, some strong, questionable desire. I guess the design might be part of it, especially the black ones, or maybe it's just my inner hipster crying for attention and wanting to be different, but there's something there. Still in all likelihood, I'm not getting a MacBook unless I find a decent one for under $250.
As for getting a desktop, I've considered doing that but at the time I have to have a laptop because I don't have home internet and I have to be able to lug whatever I'm using to the library.
Just curious, what laptop would you suggest for these needs? I'm looking for something under $250 with at least a dual core processor, upgradeable to 4GB of RAM, and I'd prefer a non-integrated video card since some games I like to play don't work on those, like Worms Armageddon and Minecraft.