If the hospital is connected via a good LAN, you may not need to go C\S, and it is quite possible you'll get better performance with VFP alone. However, if bandwith is an issue, you'll probaly benefit by storing your data in SQL Server. There are a lot of other benefits to be derived from switching to SQL Server, but I'm only talking about performance.

Whether to go with VB to VFP on the front end depends mostly on what you are the most comfortable with. After all, the best tool is the one you know the most about. Decide what you like, and stick with it!

Personally, I wouldn't go to 3-tiers unless I was developing a web app. All my stuff runs either on a LAN or WAN so I have been happy with 1 and 2 tiered solutions.

Regards,
Charlie