The memory I would not worry about unless it is more than you have allocted to SQL. What version of SQL are you running? I have had a simialer problem...

The optimization and integrity checks will cause your database to slow down. The jump in the memory utilization you are talking about is normal from what I have seen. Check...

The optimization and integrity checks will cause your database to slow down. The jump in the memory utilization you are talking about is normal from what I have seen. Check...