MOD Chip Questions (Hopfully not a stupid ones)

[Taiso]

Alright, I have a couple questions about mod chips.

1. Can you play backed up games on XBL?

2. I've seen a switch that can be installed on the xecuter to turn the mod chip off (I think they feared XBL detecting the chip) is that a good idea to install that?

3. Is the X ecuter 2 my best bet if I just want to run burned games.. none of that dashboard replacing or playing games off the HD?