>I mean, what´s the best choice?
>
>* Render HTML output within my components and return this HTML to be printed with a Response.write()?
>
Middle-tier components aren't supposed to return any presentation code.


>* Return a XML string, and make the rendering in ASP.NET? If so, what I must use? MS XML Parser? Or is there a better tool way in VS.NET?
>
Plenty of classes to manipulate XML in the .Net framework.


>* In ASP, I was used to return ADO RecordSets in some situations... I think this isn´t good anymore with ASP.NET... am I correct?
>
Well yes and no. You still can reference and use ADO in your .Net code but the ADO recordset are useless when working with ADO.Net.