Scottish fans are passionnate about football; unfortunately the atmosphere in their stadium is usually average, not to say bad. This is probably due to the very strict policy within their stadium: You have to seat at your own seat, you can't stand, you can't smoke,..., and you'll probably be rudely "assaulted" by a steward in less than 5 seconds if you're a stranger and don't know about that. The cheapest ticket is about three times more expensive than in most countries, so ... no need to say Scotland is definitively not the best destination if you want to know a good atmosphere.
however, scottish fans are usually very good supporters at european games and are always a few thousands all over Europe to follow their team.

Best games:

If you still want to go to a football game in Scotland, these ones should be the best ones to go: