New laptop advice.

Do NOT go with a netbook. They can't render 3d as effectively as necessary. As for your poor battery life, 4 hour battery life is the advertised battery life when your notebook's screen is dimmed and you're doing basic computer work; gaming is not included. If you're doing basic stuff, the battery should last between 2 and 4 hours under ideal user conditions. This means: No virus scans, no defrag, no DVD watching, no gaming, and light wireless usage for internet.

The circumstances you're putting your laptop under are not IDEAL conditions, your battery is doing the best it can for the situation you've put it in. If you want to extend, do deep cycling of your battery by discharging it as far as it will get (til your laptop shuts off) then charge it completely... Do this 3-4 times and your battery life should improve. Also, don't straight-charge the battery (charge without use) when it's not less than 15% battery life remaining, as this will shorten the overall lifespan of your laptop battery.

Your laptop has a dedicated graphics card in it, there's another reason your battery life is poor. It's also an AMD/ATi, they've been known to hog more power than nVidia. Lastly, you have a 320 GB rotational harddive; want more battery power? Drop $300 on a solid state drive.

There's only a sliver of truth in all this, I'm afraid.
I don't know about the States, but here in Canada, many manufacturers, including: HP/Compaq, Acer/Gateway/E-Machines, MSI, and Lenovo, actually UNDERSTATE their machine's battery life, for Intel Core i3/i5 based computers anyways. I've seen spec pages with as little as 2.5hrs rated, but in reviews, the laptop lasted for 5hrs doing heavy flash based web surfing, straight. My netbook was rated for 2.5hrs, I can easily push 3hrs out of it Youtubing.

Do NOT, I repeat, do NOT do deep discharges/recharges more often than every 30 charge cycles, it actually harms the Li-ion (or Li-polymer) battery more (not to mention they don't suffer from the 'memory' effect). The Li-ion and Li-polymer batteries will last the longest if their charge levels are held around 40%, at 100% the Li-ions will be too excited and bounce all around, and at 0%... it might never charge again. It is recommended to recharge your battery at as high a % as possible, if you are constantly using it. If you want more information on this, just Google 'Laptop battery care' and all of them will state roughly the same thing (but, please, don't put your battery in the fridge, that's just being paranoid).

And by the way, no, he DOES NOT have a dedicated GPU, if you don't believe me, check this out, the 4250 is an onboard GPU.

SSD vs HDD, the argument is pretty redundant, the Seagate Momentus 7200.4 750GB will use at most 5W at startup, 0.95W idle, and 2.5W average under load (look here). The Momentus 5200.6 320GB only uses 1.78W on average under load. A SSD uses 2W under load, and 0.5W idle (claimed by OCZ, SSD maker, here). As you can see, a SSD will not help battery life by much, it consumes maybe 1W less on average while the CPU + Chipset itself may use something as high as 40 ~ 50W. And, really, installing a $200+ component in a $500 laptop is really, redundant, unless you absolutely NEED the performance boost (which, even then, it probably makes more sense to just buy a new laptop).

The bottom line, don't let marketing schemes fool you. Practically any Core i3/i5 based laptop will have a battery life of 4 ~ 5hrs on a 6 cell battery. AMDs are not great for battery life, but with the newer processors, they are improving (still don't recommend you getting one if you are worried about battery life).

Edit:
Regarding the netbook statement...
Effectively? Lolololol.
You are talking about a laptop that is <1.3" thick with hardware technology that was released like 3 ~ 4 years ago, all cramped into an area of no bigger than 10.5" x 5.5", of course it wouldn't be as powerful as, say, a GTX 480.
But come on, this is Maple Story that we are talking about, the client has been barely touched for years. Maple runs fine on my netbook, albeit a little choppy in more crowded maps, but it gets the job done. I'm pretty sure that I can do a Zakum Run on my netbook without many, if any, problems. >_<