Help I Have A Prob With Logic / Quicktime, Sound quality very poor Options

[daco64]

[FONT=Times] I use logic 4.7 on a G4 laptop, when I run it the sound from the lap top ( using the Quicktime synth) stutters and is very poor for outputting an audio image to MD.

I have tried to use other vst instruments but I am not sure where to put them ( plug ins , sys folder ????) I would realy appreciate some help . I am using midi files to make backing tracks and need the best quality I can get from my set up . Do I need to scrap what I have and go for a hard soloution or can anyone help me out ?

Thanks