Forms Data Controls :: Ajax In Asp 1.1 / Taking Too Much Refresh And Taking Long Time?

I am making some application in asp.net 1.1 in that I am displaying data in datagrid from database. In data grid first column is of check box and radio button and in the last column we have text box now thing is that when i click on check box crosponding textbox we fill some figure and at the end we press calculate button to get total. After getting total we have to press continue button to go next step

But suppose if some body remove that check the we should press calculate button or chnage some figure in the text box then we should press calculate button again to recalculate. for that i kept autopost back on check box oncheckedchanged event and text box ontextchanged event and hide continue button so user will click calcutae button abd then continue button will re-apper

Problem it that it taking too much refresh and taking long time. So was lloking for some ajax method to use in my application.