Upgrade a database from SQL Server 2000 to SQL Server 2014
You cannot restore a SQL Server 2000 database onto a SQL Server 2014 instance. You need to restore to SQL Server 2008 or 2008 R2 instance first, then take a backup of that database which you can then restore to 2014.

There a lot of features from SQL Server 2000 that have been discontinued in SQL Server 2014.  See this list for the details about what features have been discontinued, and what to use as replacements.

Unfortunately, you have no choice but to re-code queries that use the ancient =* or *= join syntax.

SQLMag has a great article on how to do the migration.