How can I unstick my trackpad button?
Solution 1:
The trackpad getting stuck is also a well known symptom of a bulging battery in the MacBook Pros of this generation. I'm dealing with this issue myself and am very annoyed about it too, because this 2007 Santa Rosa MBP I paid for is essentially the most lemon computer I've ever owned (at least four other hardware failures besides this one).
Solution 2:
This is going to sound dumb, but have you restarted the Mac? I've had this issue on my Magic Trackpad a couple of times and the only way I was able to cure it was with a simple restart. (At first I thought it might be because I also ran MagicPrefs, but I've since removed that and the problem still occurs sometimes).
If you find a restart 'fixes' it, as I have done in the past, then it's possible that it's the software getting confused rather than a physical issue. I haven't found a Terminal invocation yet to restart the mouse driver part of the Mac but I reckon that if I found one I could probably use that to unstick the pad when the problem arises.
Solution 3:
I had the same exact problem and it was almost unbearable to search for help. I took out the battery but kept my MacBook connected to the adaptor and, go figure, it works like a charm. Time for a new battery! The bulging on my battery is very noticeable.