Wow, I just got back a huge project in C# from outsourced developers and while going through my code review my analysis tool revealed bunches of what it considered bad stuff
I think the best rule of thumb is only ignore an exception if you're completely aware of what the exception means and the possible ramifications of it. In the case of some isolated module that doesn't affect the rest of your system I think it would be okay to just catch the generic Exception as long as you know nothing bad happens to anything else.
IMO it's easier to know the ramifications in Java since each method is required to declare all exceptions it can throw so you know what to expect, but in C# an exception can be thrown even if it isn't documented, so it's hard to know all the possible exceptions that can be thrown by a method, and lacking that knowledge it is usually a bad idea to catch all.