Which raid configuration will maximize search performance (response time) for both word or linear searches? I have the option of Raid 0 or 1.
That will depend on the specific implementation. In theory both could double the read rate, although RAID-1 also provides increased reliability. Assuming the implementation can use both disks to read from then RAID-1 is the better choice.
The improvement with RAID-0 will depend on the concurrency in your application, as well as stripe size, and you end up with less reliability.