First of all, a definition of "vintage" would be helpful. Some games that were a normal part of my childhood seem to be considered ancient by some people.
My definition of vintage, at least as far as collecting games goes, is anything over 15 years. Obviously wouldn't apply in all cases, such as furniture or books, but games become outdated rather quickly.
Also just got Sinistar Unleashed on CD, it's for Win 95/98 so I'm not sure what "bit" generation it is.
A bit of a history lesson (puns!), but the whole "bit" concept for video games was pure marketing b.s. When a processor has a bit count, it refers to the number of digits it assigns to memory, and the number of instructions it can process in a cycle. If you are talking about Intel CPUs, anything after the 8086, which was released in 1979 is 16-bit. Anything after the 486, released in 1989, is 32-bit. There were some 64-bit Pentium 4's, but the real start of 64-bit CPUs was with the Core 2.
As far as video games go, they are organized into console "generations" where anything from generation 1-3 is considered 8-bit, 4 is 16-bit, 5 is 32-bit-64-bit, and after that the "bit" marketing idea was dropped.