Personal statement for college application?

I'm a senior in High School, and the topic for the personal statement was:

Describe the most significant experience or achievement and how it impacted you.



Now the problem is, I dont know what to talk about! Currently, I have three things in mind, which are:

-Experience in Summer College (I'll talk about learning to be independent and to interact with people)

-Experience in my trip to Japan (Talk about the cultural difference and my interest in them)

-Experience in my trip to an Orphanage (Talk about how I learn to value what I already have)



Well.. personally I prefer to write about going to summer college.. However, the college i went to is different from the college I'm planning to apply to... so I'm alittle worried about whether they might be offended by it..



so.. what do you think I should write about?Personal statement for college application?
go with the orphanage. it did impact you, didn't it?Personal statement for college application?
My wife is an English and she agrees, there's a lot more in the trip to Japan.