>Can indexes get corrupted even records are never appended to or deleted from a table.

Anything is possible. However if you have a quality network [no peer-to-peer], battery backups [UPS], automated shutdown when on battery for a certain length of time, and well trained users, this is highly unlikely.

>Also
>Do select statements make use of indexes at all?

Sure, if the field being filtered on in the WHERE clause has an index on it. For example:

WHERE UPPER(LastName) = 'SMITH'

If you have an index on UPPER(LastName) that index will be used. To determine the level of optimization [i.e., use of indexes], see SYS(3054) in VFP help.