CPI doesn't exclude food/oil, only Core CPI does.

http://research.stlouisfed.org/fred2/series/CPIAUCSL

http://research.stlouisfed.org/fred2/series/CPILFESL

The only major difference between CPI and Core CPI is that CPI is more volatile than Core CPI. This is why, for the purposes of year on year changes, Core CPI is usually reported. If we didn't do this, we'd get headlines like "OMFG, massive inflation, we are all doomed" followed by "OMFG, massive deflation, we are all doomed" 6 months later. Over a period of a year or two, massive inflation x massive deflation = small but stable inflation.

A better way to go would be to use moving averages, but that's too complicated to explain to reporters.

Official inflation rates often aren't a very relevant measure anyway. Better to think about personal inflation rates, depending on one's future expenses and living locations. An unhealthy 50-year-old with high upcoming medical costs has a high "personal" inflation rate, whereas someone surfing every day on a Mexican beach a low one.