I agree with March Ho in general: people are not rational about food.
That said there are two fairly different kinds of GMO, with different implications on the fears to have about them.
1) GMO embedding genes from the same species
These are not supposed to be any different from plants obtained using classical breeding techniques. The process in brief is for example: you see a wheat individual with short stems, an other with big grains. You want both. In classical selection you have to breed the two, select the descendants, breed again, select etc... until all descendants have both characters. Using GMO you can simply pick the gene you want and put it in the strain of your liking. It is much, much faster and the changes in the genome are much less than what you get by breeding two strains.
2) GMO embedding genes from other species
This can be more problematic as the gene you brought in could be from an organism nobody did ever eat, such as the Bt toxin in MON 810, hence the questions about toxicity. It doesn't mean it's toxic and the controls are very stringent about that but I can understand better why such GMO should be carefully checked.
3) The false problem of GMOs and environment
A Last problem is the indirect effect of the GMO, for example, if it's designed to be herbicide tolerant it might allow more herbicide to be poured on the plants and hence cause more herbicide residuals to be in the food, or in the environment, people then not liking GMO for environmental related reasons. But that should be addressed by checks on herbicides in food or in the environment, not by banning GMOs!
That said, GMOs have been around now for 20 years and people against GMO have a very hard time showing any kind of negative effects (see links posted previously), and some studies "proving" the toxicity have been shown to be statistically weak, not to say fraudulent.
There is no good reason to reject type 1) GMOs based on food safety and very little reasons to reject type 2) GMOs. I would personally push hard for a general adoption of GMOs bearing genes from the same species or other edible plants. It would already make a lot of things easier!