Improved battery life - HTC power widgets

[MrRedPants]

I'm trying to locate a description of what each of the HTC settings widgets do.

Add --> widget --> settings

What does the "mobile network" toggle actually turn on and off. I'm looking to improve battery life a bit. I thought that if I turned that off, it's essentially airplane mode and the phone radio is off, however I can make and receive calls. I also thought maybe it was the "sync" option, however when turned off, the sync is still enabled in the 'other' power widget so I know it's not that.

Most of my day is spent in a building with a less than ideal cell signal, but does have wireless.

So, shortened
1. What is mobile network toggle?
2. What are opinions on the ideal settings to improve battery life?

Thanks.