In theory, yes. Real simple apps with no 3rd party dependencies, probably.
In a lot of real world cases of any apps even slightly complex or with any
or a lot of 3rd party dependencies, NO.
We have tried in vain to deploy a couple of halfway complex apps and ran
into numerous issues. Dotnet framework has many "known issues" on Win9X.
Many problems with Crystal Reports on 9X as well.
Would recommend just to have a minimum requirements list for your app that
says: Designed for Windows 2000/XP/2003. Otherwise, you will likely run into
countless support issues as you try to roll it out to Win9X machines.
Microsoft will also love you for it, as it pushes the clients forward into
accepting their newer O/S's.