Win NT (Not Responding)

I have a VB application that writes an ADODB Recordset to an Excel Spreadsheet. Often in mid-loop, my program hangs and according to task manager- is Not Responding. According to my CPU usage graph, I see a spike where it appears to have maxed out,followed by a sharp decline and a flat-line at about 2%. I have already amped up my virtual memory and have 512 mb of RAM to work with. Any ideas what more I can do?