If they are indeed ASIO drivers, you're using what you should be. I have read lots of complaints here about Creative Labs' drivers. I've also read lots of griping about how bad Windows ME is.
I am assuming the problem you are having is recording MIDI performances in real-time from soft synths as you listen to what you're playing. One solution (the one I use, in fact, since I still have Windows 98 and MME drivers) is to record while listening tho the sounds on the card itself. With good Sound Fonts you can probably get a nice enough sound that you can live with it as you do the recording. Then, once ther MIDI data has been captured, reassign the tracks to the soft synths that you really want to be playing. You can set your latency very conservatively and it won't be an issue; it's only a problem with trying to play the softsynths in real-time.