Be careful of PGP disk. A lot of people have had problems with it. The obvious problem is forgetting your password. A less obvious problem is placing the encryption key on the C: drive and encrypting the D: drive. If you decide to re-install Windows, it’s easy to lose the key and hence, all the data on the D: drive.
Here’s another thought. The key to decrypt your data is generally on your computer. The key can very strong - essentially unbreakable. But you gain use of the key with a password. How secure is the password? Can a cracker program get it? If you are sure it can’t be cracked, where do you store that password? Do you use the same password for anything else? Mabye somebody can get the password from a weaker application.
OK. so you don’t put your key on your lappy. And you never have your key and your lappy in the same place (except when you are actually using the data). You lock everything down and take the key with you every time you get a twinkee or go to the bathroom. Are you secure now? Maybe. It depends on how you backup your data, and on how you backup your key.
And ... don’t forget to secure your network against trojans that can capture you data while you use it and send it on the net. Also, remember to secure your WiFi. (WEP encryption is not secure.) And don’t forget about that Bluetooth keyboard. Somebody with standard commercial equipment can read your keystrokes from a mile away. (It’s not hard, it just takes a little money.)
If you’ve covered all that ground, then maybe you have something worth protecting on your lappy. Did you know it is possible to read what your computer is doing by listening to the electrical noise it radiates? I didn’t say that doing this is easy, just that it is possible. NSA has computers they consider secure. They are not connected to the WWW. They are in a building. The building is completely covered in copper mesh, to keep that nasty radiated noise inside. The buildings are well inside the NSA compound. I doubt you could get within a mile of them.
Just because you’re paranoid doesn’t mean they aren’t out to get you.