Hello and welcome, fellow cruncher.
In order to take advantage of the charting abilites that Monarch offers, you'll need to create a summary in the Summary window, after you have imported your data. The steps required to import the data will of course vary depending upon the nature of the data source.
Once you have a summary defined (you could even try the Quick summary approach) you can click the Chart Properties button in the toolbar and review the options on the Chart tab of the dialog box.
I'd recommend spending some time with the Learning Guide PDF file installed along with Monarch.
Good luck with your efforts,
Some Monarch users find that some aspects of graphing are easier done in Excel than in Monarch itself - Excel seems that little bit friendlier at fitting things onto one page for printing, for example - so it does depend on what you want the graph to do. With 90,000 rows, however, you may well be beyond the limits of easy data manipulation in Excel, so you've come to the right place here.
If you're interested in using a graph interactively - clicking on elements to redraw or filter the data - then in the Monarch world there's Datawatch|ES Cube, or on the desktop I'd recommend having a look at Tableau.