Home.
Could go for three different ones entirely but...
1) Everton 1-0 Man Utd April 2005. Pivotal game game in our battle with Liverpool for 4th. Still the best atmosphere I've ever experienced at Goodison. Real tasty United side we turned over with the likes of Rooney, Ronaldo, Van Nistlerooy, Scholes, Keane etc.
2) Everton 2-1 Liverpool December 1992. Late Beardsley winner against the club which binned him off, he certainly didn't refuse to celebrate against his old club. Only time we've come from behind to win a derby since the World War 2.
3) Everton 3-2 Wimbledon May 1994. Shouldn't even have been at this game as me and a mate saw the huge queue for the Gwladys and disgracefully pushed in. Edges out the Rooney Arsenal goal game.
Away
I've a terrible record in games I've been to outside Goodison so hardly have a huge choice...
1) Liverpool 0-1 Everton September 1999. Was at our last win over at the tinmine. I remember having a right moan when it was announced we'd be kept in for 20 minutes after the game but it turned out to be great having a sing song on their patch having just turned them over.
2) Watford 1-2 Everton January 2001. FA Cup 3rd round tie. Pure ecstasy in the away end after a peach of a free kick from Stephen Hughes with just a few minutes left and then a diving header from Steve Watson in stoppage time rescued us after we'd trailed to Watford, then in the lower leagues, for most of the game. We went ballistic at those two goals. Memorable for me as I had my first ever Gary Ablett when I got back that night.
3) Man Utd 0-0 Everton April 2009. Possibly the worst ever FA Cup semi final. 120 minutes of total garbage. I was knackered as I'd barely slept the night before and that game hardly perked me up. Only ever seen the penalties since as I refused to watch the game itself again.