you probably want visual studio 2015 as its the last to support .net 2 and probably has most complete migration aids. as this is a licensed product, you need a visual studio subscription:
https://visualstudio.microsoft.com/vs/older-downloads/
as you have to migrate so far, it probably easier to create new 4.8.1 projects, and add the old source. if nuget was used, you will need to add current version of the packages if they exist, if not you will need a replacement.
note: .net 2.0 made use of the GAC, so dependent libraries were often directly installed in the GAC as opposed to being nuget packages. you will need to find the nuget equivalents if possible.