I don't really listen to any metal, but I absolutely love Machinae Supremacy. They're self defined as "SID Metal", they use whats called a SID Station with a Commodore 64 sound chip in it to add video game sounding effects to their songs. Whats awesome is a lot of their music is inspired by video games.
Linkin Park is nu-metal or some shit like that. Listen to songs from their early albums (Hybrid Theory and Meteora) and you'll see they are some kind of metal. Never heard of Skillet though so I don't know about them.
What u dunno about skillet!! Listen to this: http://www.youtube.com/watch?v=Kma6yeHY9Sc&feature=feedlik