Storing information

Question

I am working on a project for a game that I play.  This program would allow a user to store login and passwords for their accounts.  They would be able to give the account a name, and then enter the login and password to be stored.  They could then select the account they would like to log into from a drop down menu and it would then launch a web browser and then log into their account.  The problem that I am having is I am not sure how to store the login/pw information. 

I do not want to create an external file and save the information there, would defeat the purpose of making logging in more secure (avoiding typing in login/pw in case of keylogger).  Does anyone have any ideas of how to accomplish this?   I have looked into storing the file as an embedded resource but from what i've seen you can only read from the file then, not write to it.

Any suggestions would be much appreciated.

Justin