Education for the children

According to http://aoprals.state.gov
The education fee for the 12 and 10 years old will be 17,000, for the 14 years old will be 18,850.
The totally fee for all the three kids will be 52,850.

Language and Cultural Training

Luckily if you are going to Kuala Lumpur they mostly speak English. So there should not be a large language barrier. This does not mean there will not be a cultural barrier. You should try to take a training course for Malay Culture and here is a good website to look at.
http://www.crossculturalcom.com/index.html
This website will be able to give the help you need to know the culture of Malaysia better for your move or visit.

Incentives

Expatriates working in regional offices are taxed only on the portion of their chargeable income attributable to the number of days that they are in Malaysia.

The Malaysia Governement has initiated the Malaysia My Second Home Program that provides incentives for expatriates to own their own property in the country. Some of these include tax exemptions and allowances.

To help reduce the cost of doing business in Malaysia, expenses incurred on audit fees by companies are deemed as allowable expenses for deduction in the computation of income tax.

Last, companies that establish a training institution are eligible for an investment tax allowance for 10 years.

Visas and Permits

The visa price per year in Malaysia is about 90 Rm.

http://www.imi.gov.my/eng/perkhidmatan/im_Permit.asp

Medical Issues

All vaccinations should be up to date, but none are required for travel to Kuala Lumpur, Malaysia.

As for health care plans, the Malaysian government subsidizes public health care. However, many expatriates prefer to buy private policies. These can range up to $600 per month for a family of five.

Malaysia Expatriate

Costs in Malaysia

http://www.expatforum.com/articles/cost-of-living/cost-of-living-in-malaysia.html

Petronas MNC

Petronas is Malaysia's integrated petroleum multinational corporation. They have a presence in more that 30 countries around the world and has over 30 years of solid experience in oil and gas operations. Petronas is wholly-owned by the Government, and is vested with the entire oil and gas resources in Malaysia and entrusted with the responsibility of developing and adding value to these resources. Their business activities range from upstream oil and gas exploration and production to downstream oil refining, marketing and distribution of petroleum, trading, gas production and liquification, gas transmission pipeline operations, marketing of liquefied natural gas, shipping, and property investment.

Malaysia MNC-- AirAsia

AirAsia is the largest budget airline on the continent. It is headquartered in Kuala Lumpur, and was founded in 1993. Today, the company's commercial airplanes fly throughout Asia, Australia, and Europe. They have also used subsidiaries and sister airlines to expand their business.

http://www.airasia.com/site/gb/en/home.jsp