2 hours is not all that bad, considering various factors....
1) Age of the laptop (and particularly the battery)
2) Number of active programs running when using the laptop
3) amount of time you actively use the laptop in that 2 hours period
4) Peripherals - things like USB drives (particularly those not powered on their own), cameras, etc. that you have running all the time that obtain power via the USB port will drain your battery a lot faster.
5) OS - believe it or not, OS makes a huge difference. If you're running Windows 7, good, it is a heck of a lot more resource friendly than Vista ever was - and I am a big fan of Vista over XP simply because of the sheer volume of protection you need when running XP without taking unusual steps like running as a Limited User on a daily basis...)
6) Hardware settings for battery mode and OS settings for battery mode - things like downclocking the CPU and dimming the screen when using battery will help prolong battery life b/c they simply use less processing power, although a lot of these settings will also be tied directly to #3 as well - downclocking can be forced (IOW, run a lower clock speed when on battery always or it can be more like a SpeedStep - downclock when idle - but if you ahve a program that is always running actively (think game, background AV scanning, defragmenting, etc.) and it downclocks only when idle, well, with that program running all the time it never goes idle, and thus never downclocks.....
Let's start with some basic info, laptop model, OS, and configuration (HD size, RAM, etc.) an go from there.
Of course, you're welcome to call Acer if you'd like, I do agree that their cust serv could use a bit of help online, but I am satisfied with my dual 22" monitors from Acer, so...never really had the need to call them.