Mahesh Abnave

I have 32LB5820 Smart TV

I have few questions:

1. What OS it runs? webOS?
2. Is there any upgrade available?
3. If yes where do I find it? How to install it?
4. Does anyone tried running Plex on it as can be seen in this video: 
5. Can it record video to external USB drive?
6. Can I have 5.1 surround sound out from it?
7. How can I change audio track of dual audio video that I play from my external hard drive using USB connection?