Is there anything comparable to Visual Basic to use in Ubuntu?
Python perhaps?
Python is a programming language that lets you work more quickly and integrate your systems more effectively. You can learn to use Python and see almost immediate gains in productivity and lower maintenance costs.
Also, perhaps KBasic would be of interest.
KBasic is a programming language related to VB.NET, Visual Basic, Visual Basic for Applications, and Java. It combines the best features of those tools and comes with built-in backward-compatibility support for VB, VBA, and QBasic. It also comes with support for VB.NET syntax, functions, and similar objects and classes. It allows developers with an installed base of VB applications to start developing for a mixed-platform environment. KBasic comprises a compiler, an interpreter, and an integrated development environment.
I have never used it but you might consider Mono although I am not sure if it will work in Ubuntu.
Kylix, now as Lazarus, if you aren't tied to a Basic variant (its Pascal based)