Unfortunately CRM 4.0 has a limit if of displaying a maximum of 250 records per page in CRM in Contact, Account Views ect. It becomes a issue , especially when you have a few thousand records to look through.
A simple example is where you want to execute a manual Workflow or send an email to All Active Contacts at one time. The number of times you execute the Workflow is dependent on the number of pages in the Active Contact Window.
There are workarounds such using Marketing List etc but it involves executing additional steps, which is not ideal...
We hope this enhancement request is considered when building CRM 5.0.