I don't mind (and only these are listed because they occur during hte school year)
St Patrick's Day
I do mind Easter
Growing up all those holidays WERE secular - if not to my family then at least to my friends in some way.
But Easter was always religious. I never heard of a secular Easter - and never did I 'celebrate' it in school - it was purely religious for us, up at Dawn to have outside early morning service.
But my kid's school system has an egg hunt and egg games at school - ticks me off. I don't get how it was purely religious in one area of the country and some bizarre non-religious thing in another.