Let me start with plagiarism/academic dishonesty is a serious offense and it should always be dealt with. You said, "After working on a large project of his for about two full-time years..." this immediately puts us into a gray area. Did you discuss authorship at the start of the project and if so what was agreed then?
When I employ someone to work on a grant, that doesn't guarantee them co-authorship on everything they work on. Often I need someone to turn a crank and there just isn't the opportunity to make a contribution worthy of authorship. Other times I may not trust the person enough to do anything independently enough and therefore spoon feed them. In my opinion the extent to which supervisors "steal" the work of their advisees is often overrated by advisees, especially ones who have had a falling out with their supervisors.
You have a sour relationship with your former advisor and the first thing you need to do is to repair the relationship. Accusing a former supervisor of academic dishonesty by brandishing words like plagiarism is not helpful in this regards. Talking to him and explaining that you need to publish the work is useful.
I would suggest creating a list of all the projects that you worked on while in his group. From this list, you need to identify the publications that you can generate without needing any resources from him (i.e., access to HIS computer/software) and ones that you need to collaborate with him on. The goal is to identify all potential publications and establish authorship (i.e., what should have been done at the outset).
For each publication that does not need any additional resources, write a short description/abstract about the key findings, propose an author list and order, provide a time line until submission. For these publications, you should be the only one responsible for anything on the time line (apart from providing feedback on drafts). Ask him to provide feedback on the key findings, author list, and time line so that you can tailor them to better fit his needs.
For each publication that requires additional resources, you need to remember, he can ignore your previous work and just regenerate it and write the publications on his own. What you are offering is a collaboration. Again, you need to write a short description/abstract about the key findings and the additional work required, propose an author list and order, and provide a time line until submission. For these publications, the more you expect of other and the more resources you need, the less enticing the collaboration is.