I don't believe you can get VIsual Basic 2005 as a separate product anymore. You have to either get Visual Basic 2005 Express Edition or get Visual Studio 2005, which includes Visual Basic 2005.
Visual Basic 2005 Express Edition is free, Visual Studio Standard Edition 2005 is $299. Professional Edition is $799.
Visual Studio includes all products, the express editions are single-language each.
Express Edition has no support for Mobile Devices.
Express Edition cannot create/modify tables and stored procedures on remote databases.
Express Edition has simplified MSDN documentation.
Express Edition does no provide the Class Designer or Object Test Bench.
Express Edition does not support Macros, Add-ins or Packages (partner products).
No Source Code Control is supported in Express Edition (it still costs extra in the Standard Edition, but at least it is supported).
No 64-bit compilation in Express Edition.
The Standard Edition includes SQL Server Express Edition, but that isn't important since you can download it and use it with Visual Basic Express Edition.
Professional Edition also supports XSLT, Crystal Reports, and Remote Debugging. And it includes SQL Server Developer Edition.
There are also licensing issues. You're not supposed to use any product generated in the Express Editions in a professional way. It's really meant for learning and for "developer hobbyists".
All that being said, the Express Editions are a great way to learn. You could easily learn with them and then move up to the Standard or Professional Editions at a company. I use Professional Edition at work, but for my personal home projects I use the Express Edition.