Can't Figure Out If My Macbook Can Upgrade , currently running 10.6.8 and wanted to get latest version os but can't upgrade current os Please Help !!!!

You should be able to.

MacBook Air (Late 2008 or newer) model number 2,1 or higher

Your Mac needs:

• OS X v10.6.8 or OS X Lion already installed - which you are.
• 2 GB or more of memory (More is better - 4 GB minimum seems to be the consensus)
• 8 GB or more of available space

If you need/want more RAM, the 2 places I’ve seen recommended most to buy reliable RAM are below. I have purchased RAM serveral times from Other World Computing and have always been very satisfied with the product and service.

Crucial

Other World Computing

Check to make sure your applications are compatible. PowerPC applications are no longer supported. Application Compatibility

You can also check which applications are PowerPC by going to the  menu, select About this Mac, click on More info…, then click System Report and select Software/Applications.

If you have applications that you want to use that aren’t compatible, you can retain Snow Leopard and create a new partition to install Mountain Lion on or you can run Snow Leopard server in a virtual mode.

If you can/do upgrade, I recommend you make a copy of the installer and move it out of your Applications folder. The installer self-destructs. The copy will keep you from having to download the installer again. You can make a bootable DVD/USB stick to install using this free program.

Bootable Drive DVD or USB Flash Drive – Lion Diskmaker

You can upgrade to Mountain Lion

Upgrading from Snow Leopard to Mountain Lion

You can upgrade to Mountain Lion from Lion or directly from Snow Leopard. Mountain Lion can be downloaded from the Mac App Store for $19.99.

If you sign into the App Store and try to purchase Mountain Lion but the App Store says your computer is not compatible then you may still be able to upgrade to Lion per the following information.

Upgrading to Mountain Lion

To upgrade to Mountain Lion you must have Snow Leopard 10.6.8 or Lion installed. Purchase and download Mountain Lion from the App Store. Sign in using your Apple ID. Mountain Lion is $19.99 plus tax. The file is quite large, over 4 GBs, so allow some time to download. It would be preferable to use Ethernet because it is nearly four times faster than wireless.

OS X Mountain Lion - System Requirements

Macs that can be upgraded to OS X Mountain Lion

1. iMac (Mid 2007 or newer) - Model Identifier 7,1 or later

2. MacBook (Late 2008 Aluminum, or Early 2009 or newer) - Model Identifier 5,1 or later

3. MacBook Pro (Mid/Late 2007 or newer) - Model Identifier 3,1 or later

4. MacBook Air (Late 2008 or newer) - Model Identifier 2,1 or later

5. Mac mini (Early 2009 or newer) - Model Identifier 3,1 or later

6. Mac Pro (Early 2008 or newer) - Model Identifier 3,1 or later

7. Xserve (Early 2009) - Model Identifier 3,1 or later

To find the model identifier open System Profiler in the Utilities folder. It's displayed in the panel on the right.

Are my applications compatible?

See App Compatibility Table - RoaringApps.

For a complete How-To introduction from Apple see Upgrade to OS X Mountain Lion.

You certainly should be able to, here are the requirements.

http://support.apple.com/kb/HT5444

Whether you would want to is another question. You have the minimum amount of RAM required and you can't install any more on the Macbook Air. I have spoken to others who have not been happy with system performance with only 2gb of RAM.