Despite occasional mentions in gaming forums, there is no officially released Nintendo Wii game titled "Dr. Feelgood Sims 2 Castaway." The name appears to be a conflation of multiple distinct titles—perhaps blending "The Sims 2: Castaway" (which did release on Wii in 2007) with "Dr. Feelgood," a phrase more commonly associated with music or pop culture than with any Sims franchise entry.
If you're searching for a specific childhood memory or a half-remembered title, try providing these details:
With a bit more context, the actual game—whether it's a Sims title, a lookalike, or something else entirely—can usually be identified quickly.