Game Problem: wind waker fps?

hey i've recently downloaded Dolphin for my computer.. i was using stuff like vba and project 64 before and they ran with no problems at all and when i stelda: Wind waker and i cant seem to get a high enough fps.. im guessing that the average it should be is like 20-30 fps? but im only getting between 5 and 15 fps. in the menus and some places i get up to like 52 fps... is there any way i can incrrease this so it will run pretty smooth??

Few things..

1) Are you using the reversions? http://www.dolphin-emulator.com/download.html
2) Do you have a dual core? ( if no, then sorry, not going to happen, if yes enable the option to use it.)
3) are you using the open gl plug in? Its much better for speed in that case.