If you are doing a disaster recovery of an entire SQL 2005 cluster, can you just install SQL server and restore the system database to get the configuration?

Yes. YOu are correct. YOu need to rebuild the SQL instance and restore your system and user databases.

In the cluster if one node fails second node will take over and runs. If second node also fails that is complete down.

YOu need to rebuild the SQL server and restore all databases.

• Proposed as answer by Lydia ZhangMicrosoft contingent staff, Moderator 1 hour 56 minutes ago

If you are doing a disaster recovery of an entire SQL 2005 cluster, can you just install SQL server and restore the system database to get the configuration?

You can get the configuration ofcourse but you wont get user databases you have to manually restore them. First restore master then msdb then model database.