Absolutely. Chef Mickey's opens at 5pm for dinner. You really should give yourselves at least an hour to get from the Contemporary - you need to change monorails at the TTC and then you've got to get through the turnstiles and make your way to your chosen spot in World Showcase. As it's a EMH evening at Epcot, it's likely to be busy, so I'd be inclined to go for a 5pm ADR. That way, you'll be able to enjoy your meal without rushing, but still have plenty of time to get yourselves a 'front row' spot for IllumiNations.