let me jump in before the audio snobs do...
Good sound is personal preference. Only you can decide price/performance. If a $10 transistor radio sounds good to you then you save a lot of money.
1. Most would say no. Certainly not something built well. But, you may find a mass produced item that sounds good to you. IF so, no harm no foul.
2. Surround sound needs to be connected from your box to your HT receiver via HDMI, optical fiber, or audio coax. Red and white cables wil not transmit surround sound.
3. Most TV remotes can be programed to lock the volume to one component.
4. Not sure. I don't think they have full browsers.