I have taken some photo's that I think have a lot of great qualities, except that a few seem to be dull in color or light. Part of it is because the camera did not capture them correctly or because they just seemed much more colorful in real life. Does anybody have tips to make these adjustments using Adobe Photoshop CS2? Besides the obvious saturation tool or other tools, I want it to look natural, not manipulated.

have a look through the tutorials section in the galleries - there is plenty of advice to be had in there including using CS2's auto fix correction tools.