How do I programmatically use resources to make my programs culturally aware
You can use the ResourceManager object to dynamically load a particular resource based on a selected culture. This technique allows you to develop culture-aware programs without having to recompile your application.
How do I create a custom layout engine
Chris Anderson discusses how to implement a custom layout engine and gives sample code in an article on gotnetdot.com.
Where can I get information on hosting Windows Forms Controls in IE?
These articles should give you some introduction to hosting WinForms Controls in IE: Using Windows Forms Controls in Internet Explorer Host Secure, Lightweight Client-Side Controls in Microsoft Internet Explorer
What are some things to remember when drawing in Window Forms
Check out the Painting techniques using Windows Forms by Fred Balsigerat gotnetdot.com. It is a good basic discussion of how to get the best performance from Windows Forms drawing. His hints include leveraging the power of the .Net Framework by using the proper controls and control styles as well as consolidating painting code in the OnPaint and OnPaintBackground methods.
How can I add an icon to my menu items
You need to implement an owner drawn menu to add icons to it. Take a look at the sample on .netPlus.