We have 8 day park-hopper tickets. I read somewhere that you had to buy an additional ticket to ride the rides that are open during the extended hours that the theme parks are open to resort guest.
Anyone with information on this? Any comments would be appreciated.
John
Nope! That used to be the case when they had "E-Ride Nights," but they did away with that several years ago and now Extra Magic Hours are open to all resort guests, free of charge! 
Disney also offers "hard ticket" events, like Mickey's Not So Scary Halloween Party and Mickey's Very Merry Christmas Party. These occur in the fall and winter and cost about $50 per ticket to attend. Nothing like this is planned while you're there in May. 
May 2008 CSR 
Yep. EMH's are great and free. Particularly the morning ones, although I'm not sure I could get motivated to get up early on my Honeymoon. You also get free parking if you didn't know from staying on-site!