What's the deal with Mhz? And different bands??? topic

I've read and seen about it for a while flying through these forums. What's the big deal with MHZ and changing the band to a better one. My question is as follows...
I get horrible speeds here in Colorado. also what is the code you put in. #*0011* dosent work.

ROLL THAT SHT, LIGHT THAT SHT. SMOKKKKE THAT SHT