Hmm, it's been a month after this problem was posted, but I figure it might have something to do with your keyboard. Try purchasing a new one (or picking one up from somewhere).
Offering the 3 (in my opinion) most commonly used N64 emulators seems appropriate, but this doesn't mean to exclude Daedulus, Nemu, True Reality, or any of the others. Let's hear your feedback! -Murkal