Biggest advice - don't burn yourself out. You won't be able to see everything. I stayed 7 days and tired myself out - BUT it was peak season (March), so much busier. During a less crowded time it might be just fine. I went in May for about 10 days, which I found was perfect. Plenty of relaxation time, and I saw everything - the best things more than once. The Park Hopper is usually the best way to go - it allows you to see the most. Also look into the Dining Plan - it's a lot of food, but it enabled us to go to lots of expensive restaurants we wouldn't have otherwise gone to.