NOFX and Bad Religion are awesome, Lagwagon is a bit medicore, some good songs some not so much, and they dont sound very, like, how shall i say, unique. It sounds like many other bands
Well don't have an ultimate all time favourite but within genres I can pick favourites.
At the Rock/Prog/etc. end - Muse
At the more Acoustic end - Damien Rice/Jo Mango
Instrumental Guitar - Andy Mckee/Thomas Leeb
Jazz - Sonny Rollins
And lastly because I can not think of a genre - Bright Eyes