how to use a text file as a database

Hi,

I'm just strating to work with files and databases..
In my project I'm getting a word and then search for it in my text file. The text file has just words splitted by ";" and the words are not sorted.. I need an advice, how should I use this text file?

Should I convert it to CSV file, or insert it to the database.. myself, I actually don't want to use database, I think working with files is faster and the program will be lighter.. am I right?
What kind of classes should I use to search inside the file, to make the search faster, should I use regular StreamReader or there is something else with better solution?

I will be glad for any advice.. thank you