Starter running faster than Basic/Premium is because the latter uses Aero (though Basic lacks the glassy effect), and in some cases, Aero can be faster, and in some cases (where you have a crap netbook GPU), Aero can be slower.
64 bit requires more RAM because the x86-64 ISA is physically larger than that of x86-32. So equivalent programs require more RAM (at least for the executable bits) if compiled for 64-bits, and fewer instructions can fit into the CPU's cache. Etc. For those same reasons, 64-bit programs are also physically larger and require slightly more disk space (and thus more disk access to load). However, because Windows must also maintain backwards compatibility with 32-bit programs, it must also maintain 32-bit versions of various components alongside the 64-but stuff, and that is the real penalty of 64-bit (the other stuff I mentioned is pretty minor, since, unlike 64-bit RISC ISAs, x86-64 is relatively compact).
Now, the benefits of x86-64 is faster CPU execution, mostly due to the many new general-purpose registers that were added (x86 is a pretty register-starved ISA, so those new registers can make a substantial difference, depending on the program). And, of course, support for more memory.
So for low-end computers that are memory-starved and not really that CPU-bound, 32-bit can be faster. For most moderns systems, though, 64 makes much more sense.