Hi,
Try this:
window.open('../Test1.aspx', null, 'height=500, width=1100, status=no, resizable=no, scrollbars=yes, toolbar=no,location=no, menubar=no');
[Edited]:
<asp:Button ID="btn" runat="server" Text="View" onClientClick='window.open(../Test1.aspx?ID=<%#Eval("IDColumnName") %>, null, height=500, width=1100, status=no, resizable=no, scrollbars=yes, toolbar=no,location=no, menubar=no)'/>
--Amit