Lock record

Hi people. I'm writing a client application in Visual Basic,
and I need to lock certain records (a read lock) for
a long period of time (well, from the start just to
the stop of my application) so that no one can modify
them. I've seen a lock command, but it seem only capable
to lock an entire table. I'm using ADO, and it seem possible
to lock a record by opening a recordset on it (with a
proper query) and keeping that recordset open (I think
that it's the cursor that keeps the lock on the db).
Anyone knows a different/better method?
Thanks
Andrea