1)
.Mulitiple tables provides realation so that present data.
When you have customer and order details. You want show each customer's orders details is having mulitple tables ( customer,order-detaials).

Advantages:
1. One advantage of using multiple tables is that you can add tables containing new information without modifying the structure of your existing tables. For example, to add payroll information, you add a new table to the database where the first column contains the employee's ID and the columns contain current salary, previous salary, bonus payment, and 401(k) percent.
2. Also, an access to a small table is more efficient than an access to a large table. Therefore, if you update the street address of an employee, you update only the addresses table, without having to access any other table in the database.
3. Easier data modification
4. Easier data lookup
5. Data stored in only one place
Disadvantages:
1. More complex as we need to keep relations between tables.
2. Maintaining data integrity is problem.
3. Data is scattered in multiple tables - means you need to use simple to complex joins to retrieve data

2) crystall reports:
this is very power third pary control of vb.net.(offcourse it is made as integral part of dotnet..still you need to buy it if you want distribute your application ).

****advantages:
this is very powerfull
easy make simple to complex reports
exporting reports into exel,text and pdf formats.
***disadvantages:
no source code is provided.so you can modify to your requirments.
you need to have laterst updated version
you need to pay for support

3)

ClickOnce, part of version 2.0 of the Microsoft® .NET Framework, allows you to deploy Windows-based rich client apps to a desktop by placing the application files on a Web or file server accessible to the client and providing the user with a link.

It allows a user to download and execute a rich client application over the Web, off a network file share, or from local media, and the app can subsequently be run offline. It offers a full Windows user interface running on a desktop, while allowing single server deployment of application files and updates. Client applications are automatically deployed and updated on the user's machine from the deployment server in a safe way and will not affect other applications or data that already exist on the machine.

e.g if you want deploy your new application clickonce is best method.
and also if you want to update the verion clickonce is most suited methods.