I'm still not clear what you want to do. If you already have a working select list, then a user selects an option by clicking that option. Surely you don't want to select an option when the user "hovers" over an option. That would render your select list unusable, as a user could never browse through the option list. The first one they touch would get "selected".
If you code the "onmouseover" handler for the select control, the user won't even be able to see any of the options. The event will fire as soon as the mouse enters the control; none of the options will have a chance to display.
That leaves you with coding "onmouseover" for the individual options. You can do that, but again, the first one the user touches will trigger the event, making the control virtually useless.
That isn't how Google Suggest works.
Please try another explanation. Use short, clear sentences. Explain each step. Tell us what you have already have working, and what isn't working. Show us small code sections to illustrate.
If you'd like to do me a personal favor, please capitalize "I" in your postings.