Your pictures didn't come through, and your description of the job is pretty vague. I can give you some general information, but there may be other things to consider.
You have to shut the water off at the water meter. City water departments sometimes do not want customers to have a curb key. There are two ways to deal with that. Their way which is to have there employee come and shut valve and reopen it when the job is finished, or my way which is to obtain your own curb key. I had to have one made by a friendly welder.
Once the water is off, you have to remove the old valve, but here's where the fun can begin. You say the old valve is rusting and that make me wonder if you have galvanized pipe. If so, you may be opening a can of worms. Galvanized pipe has an approximate life span of 40 years. You may be looking at replacing the entire line from the meter to the house. If that is not immediately necessary, I would install a 1/4 turn ball valve. If you're connecting to copper, then you just sweat the valve on, and praise the Lord you don't have to put a new line in. You do have to the street valve 100% off so the pipe is completely dry. When I did this, if found my street valve seeped a little so I had to devise a way to keep the water out while I soldered. I made a swab from an old towel and fastened it to a heavy wire. I inserted the swab deep into the pipe, put a threaded male adapter over the wire, and sweat the adapter on to the pipe. Then I just pulled the sway out, screwed the valve onto the adapter, and had beer. I had to keep the swab straight so it would come out without jamming. Of course, this was into a 1" copper pipe. Sweating 1" copper isn't that much different than 1/2" or 3/4", clean both pipe and fitting well, flux, apply heat to the fitting until the solder flows. May have to move the torch around the fitting a tad more on 1" than smaller sizes, but same principles apply. Hope that covers your problem.