Hmmm...Im no plumber, but I just had my water service replaced. I dont know where you live? but you mentioned freezing? If thats the case, I would think your water service is deeper than 2 feet. Mine was more like 6 feet deep. I had the pros do it..but I watched them. What they did was break up the concrete from inside the house, dug with a backhoe down to the service line...my case was galvinized. Then so as not to have to remove my front porch, they cut off the existing line and slid aircraft cable through into the house and with the old line and the cable...they used the backhoe to drag the new service into place without tearing out my front porch. In your case, you may have to dig down right at the foundation and find where it enters the house. Here is the problem....if you dig at your exterior water box, or shut off and do damage...its big trouble. Mine, in fact had a hole in the service just before the water box (City side) so they had to repair it and replace the water box, prior to my guy installing the new service. Im pretty handy like yourself...but if I had have dug that and called the City, you know for sure they would have blamed me...and Id be on the hook for the bill. Its was a bigger job than what I first thought....as I was thinking of doing mine as well....glad I paid to get it done!!! Maybe you can do your own trenching after you have the water shut off and save yourself some money on that...but I would definately have a plumber do the connections, permits and locates...cause your messing with all sorts of possibilities of problems. Material wise what you use...Im not sure, but Im sure a plumber here will advise you on that.