Using Excel 2000

I am attempting, what is fast becoming apparent to be a lifetime study, to
learn about PivotTables/PivotCharts - they are powerful and facinating. I
am not a novice with Excel.

However, no matter the dataset or configuration of resulting array; whether
attempting chart after table has been created or selecting "PivotChart (with
PivotTable) at the beginning, when attempting to create a pivot chart from
my data this error occurs: "Cannot apply the default chart type to the
selected data."

I cannot find an "option" or configuration that would disallow creation of
charts or change "default chart type". So, are there any ideas as to what
the problem may be - user brain fart notwithstanding?

TIA