Should I use the watchdog timer in every arduino project?

I've done 2 arduino projects so far and both of them while everything runs fine - I find after a few weeks of running the arduino seems to freeze up. I"m not sure if its due to my bad coding or memory leaks or something similar. A reset brings everything back to life.

I've been thinking that the watchdog timer would solve my problem when the code freezes it resets the arduino - I know the first prize is to try and figure out why is crashing.

How many of you use the watchdog timer? Should I be including the WD in all my code by default? I've got a few projects where the arduino runs 24x7 and don't want to have to manually reset it every few weeks.

I know the first prize is to try and figure out why is crashing.

Yes, it is. If a fresh set of eyes might help, we’re often willing to look at your code, if you don’t mind that we laugh at/criticize (I mean critique) it.