Both WoW64 and Wine provide an environment that pretends to be 32-bit Windows and presents the Win32 API, but neither one is actually Windows XP. I've had pretty similar experiences trying to run old win32 games on both systems (i.e. it's hit or miss) but Wine has the significant advantage that it will allow a program to think it has admin privileges when it doesn't. Also under Wine, I've had better luck running games from ISOs I've ripped, where I have to insert an actual CD in a physical drive for the program to run under Windows.
