First, the unimportant point: ND plays in California the Thanksgiving weekend every year. One year it's Stanford, the next USC. The return game for each school is normally October in South Bend. I think from time-to-time Stanford sneaks into September. Not that it matters.
There are a lot of great coaches, and they wouldn't all be good everywhere. I think Meyer is in the discussion because his skill set appeared to work everywhere he went.
Xs and Os are a small part of the overall picture in college ball because the talent levels are so disparate. That's why Michigan and Ohio State will rarely truly struggle--their recruit pipeline just has better athletes than most everyone else in the BigTen. See below.
Recruiting and personnel management (both players and coaches) are the biggest issues: getting the best players and putting them on the field in a place to succeed. But recruiting is different at a blue chip than at a rebuild, or, frankly, any lower tiers.
Carroll was a great recruiter and did a great job of picking the right people out of that talented pool to put on the field.
The marketers of the world will love this, but I believe it: your brand matters. What Alvarez and Snyder did was build a brand for their program. Alvarez had the lunch pail boys--which fits perfectly with Wisconsin's mindset (the state, not just the university). It also fit with who he could recruit--and continues to. The program has stuck to that mold and succeeded wildly with it. I also think Alvarez hit his ceiling. If Notre Dame had considered him instead of Davie, I think he would have succeeded there, probably similar to a Stoops at Oklahoma: consistently very good, sometimes great, but not on a top-5 finish every year level.
All the best programs have their brands--and for the true blue bloods, it's what makes the Helmets the Helmets: thirty years after its last MNC, ND can still recruit at the highest levels; even Bob Davie and Charlie Weis could.
And coaches have their brands, sometimes effectively passed on. Carroll had the collection of pure athletic talent at USC; Schellenberger, Jimmy Johnson and Dennis Erickson had the bad boys at Miami; Devaney and Osborne had the triple option and the blackshirts at Nebraska; John McKay and John Robinson had Tailback-U; Bowden built the FSU brand--and no one has truly been able to maintain it; Paterno built PSU's brand, including Linebacker-U and the jury is out on whether Franklin can maintain it--but early returns are promising. Lou Holtz had his brand, which worked well everywhere--best at ND, which has its own special sauce--but ran out of gas (everywhere that he stayed long enough, including ND).
I think part of Spurrier's downfall (meaning what keeps him out of the pantheon in my mind--he was undoubtedly a great coach) is that his brand was Xs and Os, which only gets you so far without the talent (and obviously he had some great talent, but not on the same par as some of these guys).
Carr, Tressel, Schembechler, Woody Hayes, Lou Holtz, Phil Fulmer, Frank Beamer, Gene Stallings, Vince Dooley, etc.: those guys were all very good, but not the very top tier.
I agree with the earlier post that discounts the earlier eras--the times were much different then. Though undoubtedly Bear Bryant, Knute Rockne, Frank Leahy, Fielding Yost, etc. were great coaches for their day.
Switzer has to be up there. I don't think Stoops is; he's in the conversation because of his longevity in a time that most coaches didn't have that, but he didn't have the kind of consistent elite success that some others have. I put Bowden up there because of his amazing run at FSU: 14 seasons in a row finishing in the AP top 5. Wow. Meyer is in the conversation, for sure.
And I think Saban's accomplishments outpace all of them by a significant margin. In the last ten years Alabama has finished in the AP top 10 every year, won five national championships, and finished second two more times. The five national titles elevates him above Bowden in my mind, though Bowden more or less built FSU, so that's got to be considered. I think he's my #2.