What to say in a "cold call" email?

I’ve been with my company as a full-time employee since December and, prior to my current status, I had done two internships with them while still in college. I absolutely adore my current role; however, it’s only a stepping stone towards my greater goals with the company.

Every August they recruit internally for one of their international business segments and this year I intend to apply. I know I have the necessary qualifications and have a leg up on most applicants as I am fluent in five languages (naturally, they tend to favor multilingual applicants). However, I want to know how to make myself more competitive and what I need to do to prepare for the application process and several rounds of interview. I searched the company’s roster for people who currently hold the position for which I will be applying and I want to send them an email asking for some insider advice on how to increase my chances of being chosen.

My main questions in regards to this are:
1) Is this professionally appropriate?
2) If so, how should I word my message? (I’m a bit clueless in this matter as I’ve never had to send a “cold call” email before).

Thank you in advance, your help is greatly appreciated! I look forward to seeing what you can help me come up with.