advice on citrix

we are looking for an expert of citrix and similar products that can suggest a solution to the problem described below. We have a large client/server windows application. The EXE is 20MB . The DB is Firebird. A few DLLs are used. The application is often installed in public hospitals. When trying to install the DB into hospital servers, we face several problems due to their strict protection policies. Ever time we distribute new releases, we face the same problem. It would be nice to keep the application centrally in a server of our own, that can be reached by customers thru an internet browser. This means to have a web application. Of course transforming the current windows application into a web application is no piece of cake. It took years to write the current windows versions. It could well takes years to rewrite it... We would like to test products like Citrix's They can take an existing application and immediately make it available thru an internet connection. We would like to get the advice of an expert re the following questions: 1. practical feasibility of the citrix solution 2. should a virtual machine be created for every client company ? 3. the underlying costs of hosting/ bandwidth/licences 4. products that are alternative to citrix 5. their costs 6. does it exist an 'open source' citrix ? 7. what technology is used by remote-control products like LogMeIn or TeamViewer ? 8. what's the difference btw them and Citrix ?