Could you guys resist the urge to debate with each other and try to focus on Roisin's question?

PLEASE?

Captain, I didn't even know you played fiddle...

If there's any possibility of debate, there's no right or wrong but OPINION. Correctness and style are different things. How much of the bow you use depends on your style. Bowing perpendicular to the strings is simply correct - there isn't anything debatable about THAT.

Experiment with angle of the bow - you can use the edge of the hairs to 'dig in' a bit more. You can move the bow closer and farther from the bridge to get different sounds. Some styles use rapid wrist movements and in other styles, the bow is actually bounced off the strings. Some bow two strings at once ('double stops') and some play only single strings.

My advice is to learn everything, try new things, then decide what you want to keep.