Hi Steve,
can I suggest 2 things?
1) buy bruces book on building web apps. It will save you many wasted hours of pulling your hair out and it covers the question you are asking and many more you have not thought about yet.
2) Upgrade to to NT5 although I'm not sure of the timeline for NT6 which I believe will include JQuery's mobile framework which is currently in Alpha.
If you are seriously building web apps investing in the above is a small price to pay for what you get.
Cheers,
Kev