At 03:43 PM 24/11/2000 +0100, you wrote:
1 minute load average: 4.56 5 minute load average: 6.23 15 minute load average: 5.43 ----------------------------- Why does this keep happening and how can this be fixed?
Check your logs ... it sounds like you're being mail-bombed ... been there, done that.
Unfortunately, the only advice I can give is hire an expert if you're not sure what you're doing.