[1] How much is the average house rental for 3 person (me, wife and 5y/o daughter)?
1k RM to live like a king. Am sure you can find something lower within Kulim.

[2] is it better to live at Kulim or Penang area?
Penang as there's nothing in Kulim.

[3] What is your daily transportation mode to work? Does Intel provide shuttle services?
PG and Kulim campus has shuttle between but the hours might suck. I think they are around 7 am and 7pm each. Not too sure if there is additional in between.

[4] Can somebody provide an estimated monthly budget/expense for a family of 3 person?
Depends really. If you just stay in Kulim and don't go far, 1k to 1.5K should be sufficient. I spend about 700- 1k for 2 people on PG island for food...or maybe less, pending if I feel like going for more. This is excluding housing and bills. Bills would prolly set you back 500 bucks for telco, Satellite, broadband and electric.

Anyway, where are you hired from and at what grade?