Anything special I need to know about RS232 & FT232R?
Standard rs-232 (like your IMU) and TTL level rs-232 (like the FTDI chip) are different. 

Standard rs-232 switches between +V and -V ( where V was originally 12, but now most devices will work on much lower voltages). TTL level rs-232 switches between 0 and 5V. You need an rs-232 transceiver to convert the voltages, such as that MAX3160 chip  (Though that's an unusual one - something like the max2332 is more common).

The USB to TTL level rs-232 converters like the one you linked to are are used to connect to a microcontroller, not to a typical rs-232 device.