How to change user name and password in ODBC connection

[Mehbs]

My data is in sql2k server and my users access information or running report
thru Microsoft Access 2003.

Whenever they run the report, it gives them error. So they have to uncheck
the trusted connection and enter sql username and password to get to the
data.

I do I configure and where should I change so user dont have you do this.
It is irritation.

I have one user name and password which is set for readonly in sql. I dont
see any place that I can save this username and password.

I would really appreciate if you kindly help me.

Thanks