Sure they don't read what is right in front of them. Thats because to them the center of the screen looks like a clusterfuck of text, and is hard to distinguish at first glance (we, on the other hand, are more adept readers, so we see more quickly, because we are trained at it)
Better use of higher contrast colors would help solve the problem - ie Zebra striping on tables.

People are used to searching for information: If you want to find a site, you tend to Google for it - a nice, simple, minimal form which cries "put the text in this box".
If a large search box was placed just under the menulinks, it would become very useful in the user's mind: its not a seperate search, but more of an address bar.

As for UBB code: STFW!
UBBThreads Homepage

Thoughts on forward compatability: I haven't looked at the UBB code, but either it should be templated (alright, a little doubtful), or simple DOM javascript could append nodes in the relevant spot.

Don't tell me about people who surf the web without javascript on. So what? They just get the less enhanced, no search box option. Whoopee. If a user is smart enough to turn off javascript because they are worried about security, chances are the user probably has no troubles with roaming the internet and searching for data.