I find it somewhat amusing that anyone would be interested in writing or reading this sort of advice. Getting fired is not something you should avoid. Any relationship that isn't working is better off coming to an end, for both sides. If you're stuck doing work you don't like and for some reason didn't find yet the motivation to move on, be glad that your manager did you the favour.
In the long-term, you are right. However, you are much better off sucking it up for a couple of months while looking for your next job. You avoid the been-fired stigma, and you have much better negotiating power with your next employer.
