Want to change the order of the selectors(content types) in the custom search.

Hi,

I am using custom search for searching internally and I have also included 5 selectors in the custom search
for ex 1. Core facilties
2. Forums
3. Investigators
4. Publications

these are the four selectors that appear in the drop down menu, how do I change the order of displaying the selected for ex. I want the list to be
1. Investigators
2. Publications
3. Forums
4. Core facilties.

and one more thing, the default search of custom search is the "-AnY-" which includes the entire website or all the content type which appears in the selectors, but I want to change the default content type as one of the selectors for ex Publications of the above list.

Please help me in solving this problem

Thanks in Advance.