Try this first (change all the options mentioned in this list):
- Disable VSync
- Disable the Widescreen Hack
- Set EFB Scale to 'Fractional'
- Disable Pixel Lighting
- Disable Forced Bi/Trilinear Filtering
- Enable 'Use Native Mipmaps'
- Change Framelimit from 'Auto' to 'OFF'
- Disable 'Load Hi-Res Textures'
- Disable 'Use Panic Handlers'
- Disable 'EFB Copy Regions' overlay information
- Open the Windows 7 control Panel and disable 'show shadows under windows' in the advanced performance settings
- Use a lower resolution (1024x768 or lower)
- Open the Windows 7 Control Panel, go to 'Power Options' and set the power plan to 'High Performance' (remember to keep your laptop plugged while gaming)
and see if it gets you a huge FPS boost
If that's not enough, check this one as well and see if it changes anything performance-wise:
- Use JITIL (experimental recompiler) instead of JIT Recompiler
If not, try these options:
- Open the Monster Hunter Tri game properties and enable the 'Block Merging' option
- If the game doesn't require XFB to work correctly, then go to the Direct3D9 graphics plugin properties and disable this option as well
Finally, try this as a last resort:
- Change the EFB scale setting to x1 (Native) instead of 'Fractional'