At the risk of being accused of thread necromancy, I'll give you an answer to #2

Contrary to what one might expect, the "Google Search:" string is not related to any of microb's configurations data and it is not easily configurable. Instead, it is an hardcoded string inside the browser itself; what makes the situation worst is that the browser strings are available for each supported locale, meaning that for each locale that you care about you would have to make an adjustment.

In short, the things needed to change the string to whatever you wish are:
1) write down the locale you are using
2) open a root shell to the N900 (ssh recommended)
3) navigate to /usr/share/locale/<your locale here>/LC_MESSAGES
4) make a backup copy of osso-browser-ui.mo
5) hexedit osso-browser-ui.mo making sure that the file format's structure is respected

The file format in question is the 'Machine Object' file format, which is thankfully very simple. The specification is available here.

Result in action here.