Preparing agewsie details of debtors from tally

I want to prepeare a Agewise schedule of Sundry Debtors.

For that i hv also tried :

Gateway of tally----Display----Statement of accounts----Outstanding----Group----sundy Debtors---F6-Selected Ageing by Bill Date----Period selected---After this a report is generated

In report screen ..One more column is showing i.e. "on Account " at last. So my ques is wht does this 'on account' column denotes.

Further queries:

1. For the purpose of showing it in internal audit report :Wht to select after F6 in b/w ageing by bill date vs Ageing by Due date

2.Wheher report genered after period selection can be relied upon..whether it depicts the true picture of ageing of drs...?

3. If i want it to see in Excel,then pls tell me the step by step procedure of exporting report into excel.

4.if u know suggest any other method to prepare age wise schedule of debtors from tally

5. any other suggestion u want to give..

thank you..