Melee should run smooth... should
I tried Melee on a 15" MacBook Pro (2760QM Processor) (Windows 7, x64 Bootcamp), and it ran at 100% most of the time, except for a bit of lag between menus etc.
The only problem is on a laptop the cooling is no where near as good; it could be a case of your processor over-heating that impact performance.
Try it though; Melee is relatively light in regards to say Twilight Princess or other games.
I tried Melee on a 15" MacBook Pro (2760QM Processor) (Windows 7, x64 Bootcamp), and it ran at 100% most of the time, except for a bit of lag between menus etc.
The only problem is on a laptop the cooling is no where near as good; it could be a case of your processor over-heating that impact performance.
Try it though; Melee is relatively light in regards to say Twilight Princess or other games.
Windows x64 | Intel i7 4960X @ 4.6Ghz | Nvidia Geforce GTX 780Ti | Hyper-X Beast DD3 RAM 32GB 2400MHZ