The first Terminator film explicitly states that ONLY organic objects can be transported using the time machine created by Skynet (this is probably to cover the huge plot hole of why Skynet didn't just send some nuclear weapons to the past and destroy Los Angeles instead of a single robot)
However in Terminator 2, the T-800 states the T-1000 is made of liquid metal (e.g. no organic parts) It should not have been able to be transported back to past for this reason alone.
Although the T-1000 is shown on several occasions to be as strong as the T-800 (or stronger) it never uses this strength to attack any of the main characters besides the T-800. In several scenes (including the elevator scene) the T-1000 could have easily used its strength to eliminate the protagonists, yet fails to do so.
It was made clear by Reese, a character from the first film, that Skynet, the AI which destroys humanity and creates the Terminators, has only limited knowledge of the past. Yet Sarah Connor for some reason remains in the Los Angeles area with her son who Skynet is sending robot killers to eliminate.
If she had moved ANYWHERE else in the world and changed her and her son's names, it is likely that not only would they be safe, but they would have prevented the events leading to Judgment Day (the nuclear war which allows Skynet to take over the world.)