Zenphoto version 1.3.1.2 [5831] (Official Build)

Screen show strange characters when access the page, see follwoing printscreen:

http://img808.imageshack.us/img808/651/zenphoto.jpg

Do I need to reinstall the system?

Most likely your "options" table has the field "value" set to some other character Collation than utf8_unicode_ci. Change the database to have all fields/tables utf8_unicode_ci.

You may need to drop the options table and re-install.

the whole db was already using utf8

http://img19.imageshack.us/img19/6014/zenphoto2.jpg

It's strange only happen on "Reset album thumbs" option

http://img227.imageshack.us/img227/6808/zenphoto4.jpg

the other options are normal

http://img836.imageshack.us/img836/2382/zenphoto3.jpg

Try changing the button selection. Let us know if that fixes it.

Can you kindly tell me where is "button selection" option on admin page?

Well, look at the picture you provided in the first place.