How to analyze reaction times and accuracy together?
MANOVA is definitely a bad idea given that one dv is continuous and the other is binomial. After exploring a number of different approaches to combining RT and accuracy data, I've come to conclude that the best current approach is to use linear ballistic accumulator model (e.g., see Donkin et al 2011). 

The LBA is a simple (structurally and computationally) framework that lets you speak to the different processes (info processing efficiency vs response criterion) that jointly contribute to RT and error data.

References


Donkin, C., Brown, S. &amp; Heathcote, A. (2011). Drawing conclusions from choice response time models: A tutorial using the linear ballistic accumulator. Journal of Mathematical Psychology, 55, 140-151. PDF