Perfomance tuning

Dear friends
We have one problem in our existing system.We are expecting some expert comment on this.We have one corebanking system back end as MS SQL server with IIS server.Our system is always very slow in the peak times of tranasactions.We are planning to optimize this with a short time plan .So pls give some suggestions that our DBA team can implement in a short time with SQL SERVER 2000

Thanks in Advance
Filson

A possible course of action is this:

Try to check your IIS's and SQL's processor during the peak times to see if the problem is with your SQL or IIS

If your problem is not in IIS:

Try to see if your sql server's processor is 100% or near. If it is, then your queries are probably too heavy - if it is not, then you possibly have locking problems.

Try to find if there are specific queries that are taking longer. You could use Sql Profiler for this, by specifying a duration minimum threshold for the events - for instance, only show queries that take more than 5 seconds (warning: this might deterioate even further your performance while the trace is active). After finding out the worse queries, try to understand why they are running slow - you could use SQL Query Analyzer for this, using the SP's execution plans.