My PC or a new Mac for school/gaming?

I currently have a killer Laptop I got for a steal, it is the Acer Aspire 5552g, this thing is a great gaming machine, it has very little battery life though, gets super hot, and I am wondering if it is time for an upgrade.

Acer Aspire 5552g specs:

Processor - AMD Phenom II X4 N930
Graphics Card - ATI Mobility Radeon HD 5650
Screen Size - 15.6 Inch
Hard Drive - 500 GB HDD
Battery - 6 Cell Li-on

The thing is, I am using this laptop constantly at school and the battery always runs out in roughly an hour or so when I use it. Also, it often times gets quite warm when using it for simple tasks, etc. BASICALLY, I am just wondering if getting the new Macbook Pro at this point would be worth it. The battery will last me the WHOLE work day, the graphics aren't bad at all so I could still play the odd game or two, the processor is great, and the laptop is sleek, slim, and sexy (Three S's lol).

Also, which mac should I buy? I don't think a 13 inch macbook pro would cut it, I think I would need a full 15 inch screen, but that would cost me a fortune! What do I do?!