Another Web Application server to consider may be Macromedia ColdFusion MX. ColdFusion Markup Language has a very short learning curve compared to most other "web enabling" technologies. Circumstances at our shop dictate that we find and use technologies that are easy to teach and learn since many new people are usually new kids right out of high school (this is a military installation). I have two 18-yr-old troops doing web application development and it only took about 3 weeks to teach them HTML, CFML, and simple T-SQL statements. They still have a long road to haul on learning more advanced T-SQL and database design, but they will learn that as they go. Of course, both of these kids have caught the computer programming buzz and are now attending college to get a proper education in MIS.
If you have the employee talent, then ASP.NET is definitely a good technology to use instead of ColdFusion because it is much more integrated with the OS and you may be able to use much of your existing VB code logic.
I don't recommend using the InterDev IDE either. It isn't very intuitive and the code it generates is not always readable if you need to look at it. I use HomeSite for most of my web application development because it is a dream to use when working with code. Dreamweaver is also an option if your more of a visual developer. Of course, you could also use a simple text editor like Textpad (http://www.textpad.com) or CoolEdit(http://cooledit.sourceforge.net) to do your web application development.
We only use SQL server because it has many more robust tools built in that MySQL does not. Oracle is an option if you plan on creating web application where processing volume is heavy, but I feel a good SQL Server configuration will be able to work just as well as any Oracle configuration.
I hope all this helps,
"I will not be taken alive!" - S. Hussein