If they have physical access to your laptop and some tech-know-how they will break into your user account easily. (assuming your disk is not encrypted)
Breaking into the application itself and decrypting the passwords is possible using rainbowtables or a brute force attack.
Also a lot of websites like forums store passwords in cleartext inside their cookies.
Assuming they'd get this far would mean that all of your passwords are compromised. And they will most likely get to your online back-ups.
Yes they will be able to get to them, should they have the knowledge.
What you can do
There is no way you can be 100% secure, but you can encrypt your entire OS. I know this sounds contradicted with what I said previously, but the post is about making a decoy OS and a hidden one. With luck they will stop looking for more when/if they crack the password of the first volume. Still weigh down the pros and the cons of completely encrypting your hard drive.