Kudos, Howard, for your program and providing computers to kids, especially now since you want to start into linux. Linux isn't going to be "easy" in this case, bc you will have some issues, specifically in that VB 4 apps aren't supported very well in wine (a windows compatibility suite that allows to run lots of windows programs on linux). You have a few options when it comes to your educational software.
1. You can check the app database at www.winehq.com
and see if wine supports any versions of the VB runtime. If that's the case, then you can install the VB runtime program and your programs should work fine.
2. You can look into updating your programs to a more recent version of VB, such as VB.NET. the .NET framework has been recently supported by the developers of wine, using only one extra programs (mono) as far as I know. If you can do this, it will more than likely make your headaches fewer and further between.
Other than the educational software you have mentioned, you shouldn't have any other problems with any version of linux you choose, as they all come pre-packaged with decent web browsers (firefox, konqueror, and seamonkey to name a few). You can look into Ubuntu and Fedora, as they are both well supported and well documented on their forums.
For wireless cards, you can check here, linuxforums.org and any other forums site, as well as a few driver dev sites, for information regarding the cards that are currently supported in linux. Linux is infamous for not having good support for wireless cards, but more cards are being added to the compatibility list every day.
If there are any other problems you run into or questions that you have, feel free to let us know here. There's always someone willing to help you through a problem.