i have a xbox chipped with a xecuter 2 with a 120gb hd and auto installer 2 in it
i wonder if anyone could tell me what would happen if i plugged my internet in my xbox or what it could do if i did plug it in ?
Nah, I reckon end of the world is unlikely. Don't think the little xbox is capable of running SkyNet.
In reality though, you could get access to Xbox live (if you switch off the chip first), xlink-kai for similar online gaming, if you're using one of the "pimped" XBMCs you get loads of online access to videos (google video, youtube, etc etc), updates to the Weather in XBMC, you can download game saves via Evox or Avalaunch, loads of stuff really.
If you use a router for your net access and have a PC or NAS on the same network, you can stream video and music from shares to your tv.