On the Room to Roam re-issue The Waterboys do a fantastic live version of the song Twa Recruitin' Sergeants. It's worth the price of the CD on its own.
To be honest most of the Corries songs are very goiod. I think I've got pretty much every song they recorded and there are not many bad ones among them. My favorites are the faster ones such as the two I mentioned however slower ones like Dark Lochnagar are also worth a listen. I would say the Corries are the best folk group to come out of Scotland in the last 30 odd years.
I saw the Corries live in the mid 70's and they are top class. There is loads of stuff on you tube. Check it out. Best songs (in my opinion) are MacPhersons Rant and Maggie Lauder.