Why update from NIS 2010 to NIS 2011 - Some questions

I have recently read a thread started by Lexus2456 which made interesting reading. I also went to the links given there:

 

Lexus2456's thread

 

I have the following questions and I'd be grateful for any answers you can give.

 

1. Why should I update when NIS 2010 already does all I need from a security suite?

 

2. What features does NIS 2011 have which aren't already offered in NIS 2010?

 

3. I've noticed NUA.exe in the 'Processes' in Task Manager. Can I end the task and, if so, will it go away for ever or will it return at some point.

 

4. Why is this being done without my permission? I have a dial-up connection because that's all I can get where I live and this could take ages. It's ludicrous that I have to download it before I get rid of it. I have NIS to ensure that things don't get onto my PC without my knowledge or consent, but apparently Norton itself can do as it pleases!