I wouldn't have thought you could get more 'classical' than 'All Right Now' by Free. It's a guaranteed stormer. Other good ones of theirs are 'Little Bit Of Love', 'The Hunter', 'Wishing Well' and 'Fire And Water'.
After transforming into Bad Company, stand out classics are that always raise massive cheers and create good feeling are, 'Feel like makin' love', 'Can't Get Enough' and 'Ready For Love'.
Incidentally, if anyone can transcribe any of the Bad Company songs for a beginner, that would be fantastic.