You are looking for trouble, why?

1 那位有經驗的朋友可以提供一個要準備的材料的complete list？

Since you have done several times, you should have that list already. The most important thing is: your parents need a strong tie with home country thus avoid the excuse of immigration. This tie could be: you have some other brother/sister, they have great property, they have business, etc, etc, in short, they can be here only for a short term of enjoyment, not here for long or even worse work here for you.

2 父母兩年前曾三次被據簽，是在我的身份為F1的時候。連畢業典禮都給據了。最近聽說，據簽記錄大使館在2年後會自動消調，是真的嗎？

I would not buy that. I am sure those records will be in their system for a long time, if not forever.

3 父母是否還要預約“曾據簽”的那種呢？他們護照上是有據簽章的。

Just follow the rule, do not try any trick. Even if you success, you might be punish later in your own immigration stage.

4 簽證的理由，是否可以實話實說，告訴他們我要生孩子？還是講來旅遊？

You are not kidding, are you?
The only trick you can legally use is: NO ASK, NO TELL.

5 還有什麽tips，可以分享一下？

I am not a lawyer, so do not take my word for granted, but only want to help.

Just my 2c.