Have you tried the DataFormWebPart (DFWP) before? It is basically the most basic of databound webparts, but strangely the most customizable as well.
To try it out, open SharePoint designer and create a dummy aspx page to work on / play around with. Then open the datasources pane and find the list you want to use. then click on that list and select "view data". Drag the appropriate fields onto the aspx page. You now have a (very) basic grid displaying your data.
The cool thing is though, all layout is xsl driven, so completely customizable. You can even make the xsl reusable by switching to source view and cut and paste the xs,l into a separate xsl file. To then use this file instead of the inline xsl, after moving the inline xsl, change the DFWP property xsl (that contained the inline xsl) from
<xsl><!-- .... this is where the moved inline xsl used to be... --></xsl>
to
<xsllink>/server relative url to xsl file</xsllink>
The only remaining problem is that the DFWP's datasource is now bound a single list. To do roll-ups cross site collection (if you have say multiple event lists you want to include), you need to change the DFWP's SPDataSource's select query and datasourcemode. How to do that is explained here.
Now to address your actual question: (after my blatant plug of the underappreciated DFWP :-D) The DFWP's SPDataSource basically uses either an SPQuery or an SPSiteDataQuery (depending on the datasourcemode) to retrieve the data, and you can do way more filtering wise. Either in the CAML query itself or by just filter out the unneeded rows using something like the following:
<xsl:if test="not(contains(@Title, 'Deleted:'))">
<xsl:apply-templates />
</xsl:if>
