The end of SQL Server 2005 extended support is nearing on April 12, 2016.
To accomplish a smooth and trouble-free upgrade to SQL Server 2014, you should plan for upgrade and address the complexity of upgrade for your applications.

As a provider of the SSDPS Upgrading  to SQL Server and Migrating to SQL Server engagements, DB Best (my employer) works with many customers to assess the scope and complexity of their upgrade, run a proof-of-concept, and create a detailed plan for deployment. SQL Server Deployment Planning Services (SSDPS) allows the development of a plan to upgrade and migrate to SQL Server.

Another great resource is the SQL Server 2014 Upgrade Technical Guide. This document is a supplement to SQL Server 2014 Books Online.
You can download this 429 page comprehensive guide here.

Starting in a few weeks we will keep you posted and informed of upcoming seminars and events, additional blog posts and recordings of sessions we are targeting providing you with guidance on how to successfully upgrade your SQL Server instances.