Heavy Stutters on Mario Kart Wii

[Otinademoniac]

Hi everybody, I'm pretty much a n00b around here I'm trying to play Mario Kart Wii on my Dolphin and it seems there's something wrong: the game starts smooth at 60fps, then after I choose "1 Player mode" audio heavily stutters (but I still get like 25-30fps), and finally, when the race begins everything is tremendously lagging, playing around 7-10fps.

My PC configuration is:
- CPU: AMD Phenom II X4 945 3.0GHz
- GPU: nVidia GeForce 650 Ti Boost 2Gb
- RAM: 4Gb DDR2
- OS: Windows 8.1 Update 1

Since I can usually play PC games pretty well (Bioshock Infinite or Dishonored, just to mension get easily around 45-50 fps at FullHD max settings) I don't know what's the problem. Any help? (I hope so! :-D)

Thank you in advance, in the pictures you can see my Dolphin configuration (I'm following wiki guidelines)

[Anti-Ultimate]

Dolphin isn't a PC game, as explained in 1000 other posts on this forum.

The only thing that could give you speed-ups should be setting EFB to Texture and using the OpenGL Plugin. Your PC is kinda slow for Dolphin.

[admin89]

Your CPU is old and terribly slow for Dolphin but your GPU is very good
Take a look at Dolphin Benchmark
Any CPU that is slower than i3 4130 will not run Dolphin well

[Otinademoniac]

Thank you for your answers, I really appreciate them :-)

[Otinademoniac]

Side note for anyone who'd like to play the game with rigs like mine: more than OpenGL, the game runs almost perfect (40fps, 80% speed) on native resolution using DirectX9.