>I am trying to install SQL Server 2005 on my laptop. When it reaches the form "Components to install", all options are disabled but the last one. So, I cannot install anything. I also tried with setup.exe SKUUPGRADE=1 but that didn't change anything. I have SQL Server 2005 Enterprise DVD and I am trying to install from it. What am I missing?

The Enterprise version cannot be installed on a workstation. You should install Developer version. It's almost the same as Enterprise but can be installed on a workstation.