VB... that's alright we wont hold it against you
"High church" UML says a component is a "seperately deployable" chunk of the design solution. Thereore, to be pure - the executable could (usually) be a "part" of a component, the component would also include any configuration data, registry entries, data files, dll's, help files, etc etc etc. To go further, when each of these parts is actually deployed on a "node" they become "artifacts".
In reality, (here I go again folks), the purpose of UML is to enable communication regarding the design of the system between stakeholders. So, if it makes sense for all of your audience to view the executable as a component go fo it.
The forms - at the architecture "deployment" level - could similarly be defined as
one of the interfaces. However, the user interface is usually (in my experience anyway) not of great concern at the deployment or component level. The problems at this level have more to do with internode and intercomponent communications. Please note the "in my experience" caveat above, it may be of concern to you and your audience.
hth
Bruce
