its not a small task and requires some indepth experience and knowledge, especially if you are going for a job interview. Remember, you can't lie about the things you talk about or appear to know about, you need to demonstrate it when the time comes to use it.
to read a textfile, you can use the FileStream or the StreamReader, both in the System.IO namespace but now you have to explain further about how you are trying to insert it into a database. What do you want to insert? each line of data in the textfile equivilating to 1 record? or do you want to store the file itself in the database? What exactly?
not sure how you mean reading from recursive methods from a table to VB.NET. if you are hooking up to a database you have several methods on how you can read data. Either by filling it using a dataset and using a dataAdapter or using the DataReader to read each row of data retrieved and going through it by column using a while loop for example
in terms of xml, what kind of xml? Serialized? Settings? Dataset xml?