Casper is quite right -- without a clear description of your problem this isn't likely to be a terribly productive exercise.
OTOH... as described improving your configuration is something like shooting fish in a barrel
0) Upgrade. 9.1C is ancient, obsolete and unsupported.
1) Dramatically increase -B. 100000 is a good start. 200000 is not unreasonable.
2) Set -spin to something between 5000 and 20000. Personally I recommend the lower end of the spectrum for up to date releases. But you are running 9.1C which is ancient, obsolete and unsupported so a higher value may be ok.
3) Increase your bi cluster size. Start with:
proutil dbname -C truncate bi -bi 8192
4) Start a BIW and at least one APW.
5) You don't mention whether or not you are running after-imaging. You should be.
Everyone with data that has value should be.
These are pretty basic. You can safely take these steps without knowing much at all about your application or the specific performance problem.