would these batteries be sutable?

ah, sorry, not awake :)

to much for my 15a esc to handle but these will also have 25a fuses in to cope with the extra voltage

The 15A electronizes can handle 24v so either will be fine

ah, ill got for the larger then :)

would bigger fuses be needed or not?

It doessn't really matter if they are in the wiring I would keep the in case the motor stalls

i used fuses for a while but then dropped them when one blew in the middle of a fight. Never had a 15A electronize fail on me even after shorting the BEC accidentally. Had two stalled drill motors on two seperate electronizes and they didn't blow.

ah, thats useful to know.

can anyone give me any advice on how to make my own 18v nimh batter pack from cells? i cant to explore all options before i pay out

get all the cells in the formation you want, solder them together. you can use small peices of wire to join cells. just make sure you get the posatives and negatives right.

anyone know of a good diagram to show the best way to wire them?

also, would running my 2 motors and actuator of 1 18v battery be any different performance wise in terms of speed and charging etc to running 2 9.6's in series?

i would recomend the 2 9.6s. it would be probably be easyer

speed wise yes you'd see a slight increase as taking the none charged values you get 18v compared to 19.2

how long the battery will last and how long it takes charge depends upon the mah rating of the cells, the charge time is also altered by the amps you charge at