If you need to save sensitive information in text files, use
Steganos' LockNote program to password encrypt and protect the data. Uses AES 256-bit encryption technology.
Don't use IE, it sucks as far as security goes which is everything if you bank online. Use FireFox with these add-ons:
Key Scrambler - Although this add-on is not open source it's free version does protect you from key loggers when you are about to enter your user id and password on any web forms online. It encrypts your key strokes from the keyboard driver all the way to the browser. The commercial version does this for all your OS key strokes.
NoScript -This is another awesome security add-on. This one will not allow any website to run scripts unless you tell NoScript to allow them to do so.