If you're new to ASP.NET 2.0 development then you might want to check out these super high quality video series on ASP.NET 2.0 – the How Do I video series.  It covers many of the common tasks and amazing productivity benefits of the platforms in short 15 minute digestable videos:

  • ASP.NET HOW DO I Video Series: Caching (Part 1)
    This video is part one of a two-part series introducing the new caching features of ASP.NET 2.0. Start with a demonstration of Page Output Caching followed by an overview of the new ASP.NET 2.0 Database Caching support for SQL Server 2000 and SQL Server 2005. Topics include using the aspnet_regsql.exe utility to add SQL caching support to a SQL Server database, creating a SQL cache dependency to eliminate unnecessary connections to the database, enabling table-level caching, and enabling enhanced caching support using SQL Server 2005 Change Notifications.   
  • ASP.NET HOW DO I Video Series: Caching (Part 2)
    This video is part two of a two-part series introducing the new caching features of ASP.NET 2.0. Topics include the new Partial-Page Output Caching feature of ASP.NET 2.0 followed by an overview of the Cache API, which demonstrates how to efficiently bind a data control to an XML file.
  • ASP.NET HOW DO I Video Series: Create a Full-Featured Customer Login Portal
    Get an overview of the major features and improvements introduced with Visual Web Developer 2005 Express Edition and ASP.NET 2.0. Follow along through the creation of a fictitious customer portal to learn about topics including Master Pages, Themes, database access, Membership, Roles, the Web Site Administration Tool, site navigation, and user profiles.
  • ASP.NET HOW DO I Video Series: Data
    This video illustrates how simple it is to create data-driven web sites using Visual Web Developer 2005 Express Edition, ASP.NET 2.0, and SQL Server 2005 Express Edition. See the integrated data editing support provided by Visual Web Developer that simplifies database creation and population using the Database Explorer and DataSet Designer. Explore how easy it is to create a master-details view with support for filtering, sorting, paging, and editing with no code using the DropDownList, GridView, DetailsView, and ObjectDataSource controls.
  • ASP.NET HOW DO I Video Series: Form Building for a "Contact Us" Page
    This video introduces a number of the new ASP.NET 2.0 controls for building forms to collect information from the user, validate that information, then send a confirmation e-mail message. Features covered include the Wizard control, Validation controls, and the System.Net.Mail classes for sending e-mail messages.
  • ASP.NET HOW DO I Video Series: Localization
    This video is a tour of the web site localization support in Visual Web Developer 2005 Express Edition. Learn how to create culture-aware and locale-specific web content with ASP.NET 2.0 with no additional code. Topics include the new declarative binding syntax, page-level vs. application-level resources, and using the rich resource editor.
  • ASP.NET HOW DO I Video Series: Master Pages and Site Navigation
    Create a Web site with a consistent layout and design across all its pages using ASP.NET 2.0 Master Pages. Become familiar with the enhanced designer support for creating and consuming Master Pages in Visual Web Developer 2005 Express Edition. See the improved Table Editor and Style Builder in action and learn how easy it is to add navigation to a Web site using the new TreeView and SiteMapPath controls.
  • ASP.NET HOW DO I Video Series: Membership and Roles
    Learn how to secure a Web site using the new Membership and Roles features of ASP.NET 2.0. Topics include user registration, password recovery, and restricting access to content with roles. Get a tour of how the Web Site Administration Tool simplifies user account administration and makes it easy to control content access permissions.
  • ASP.NET HOW DO I Video Series: Profiles and Themes
    Discover how to create a customizable Web site using Visual Web Developer 2005 Express Edition and ASP.NET 2.0. Learn how to use Profiles to collect per-user configuration information and apply Themes to extend a consistent look-and-feel throughout the Web site.
  • ASP.NET HOW DO I Video Series: Tips and Tricks
    This Tips & Tricks video covers many useful techniques for enhancing ASP.NET 2.0 web sites using Visual Web Developer 2005 Express Edition. Topics include encrypting sensitive information stored in web.config, maintaining the browser scroll position across postbacks, posting content to a different page, setting focus on a specific control when a page is loaded, creating a bulleted list of hyperlinks from an XML file, working with the file upload control, simplifying complex URLs using URL remapping, and using the MultiView control to switch between groups of content programmatically.
  • ASP.NET HOW DO I Video Series: Web Parts and Personalization
    This video shows how to use the new Web Parts and Personalization features of ASP.NET 2.0 and the designer support provided by Visual Web Developer 2005 Express Edition to build customizable web pages whose content and layout can be modified by the user. See how Web Parts enable the user to add new content to a page on-the-fly and restructure the page in the browser using drag-and-drop.

Another great set of resources is the Microsoft® ASP.NET 2.0 Webcast Series, sponsored by Microsoft, Dr. Dobb’s, and O’Reilly.
Choose from 45 webcasts organized by track—JSP, PHP, and ColdFusion. Each track has been designed to take advantage of your existing Web development skills and includes insightful content contributed by Dr. Dobb’s and O’Reilly. Select the track you’re most familiar with, and then pick the webcast topics that’ll make your skill set even more versatile:

When you attend three webcasts, you’ll receive an ASP.NET 2.0 Development Pack, including Microsoft Visual Studio® 2005 Standard Edition (Not for Resale), five chapters of Programming ASP.NET 2.0 Core Reference, by Dino Esposito, and more.

 

On the security side of things there's the ASP.NET 2.0 Security Guidance Library:
 
Key Recommendations/Guidelines:
• ASP.NET 2.0 Security Guidelines
• ASP.NET 2.0 Security Checklist
• ASP.NET 2.0 Security Practices at a Glance
 
How Things Work:
• Forms Authentication Explained
• Windows Authentication Explained

Security Engineering

Web Application Security Engineering:

• Includes threat modeling web applications, security design review, security code review, and security deployment review.
• Home: http://msdn.microsoft.com/library/en-us/dnpag2/html/WebAppSecurityEngIndex.asp

ASP.NET 2.0 Security Code Review:
How To
ASP.NET 2.0 Question List

Cheat Sheets
• Cheat Sheet: Web Application Security Threats, Attacks, Vulnerablities, and Countermeasures