If you are going to make cooking a smooth passage of activity, these are number one. Casserole pan/Dutch oven. This is the one I use. Got it from M and S for £50. Cooks on the hob top and goes in the oven. This will usually see action 3 or 4 times per week. If you do not have one or do not want to get one, a big hob top pan will do for most of the things on the menu.
If you do get one, or have one, get some oven gloves to go with it.