You found the 6-in-1s that many of us use. You are lucky because you found them locally in a store. I ran out recently and had to order them directly from Escalon since they are unavailable to me locally.
The ground unpeeled 6-in-1s with puree will be thicker than canned whole or crushed tomatoes, which will ordinarily have a higher water content than the 6-in-1s you found. The 6-in-1s can be used in most sauce recipes, but you may have to make adjustments to the liquids to get the consistency you want.
Many of us use the 6-in-1s on our pizzas right out of the can, with some herbs, garlic, red pepper flakes, etc. The consistency is just about right (although you may want to drain them a bit for use in deep-dish pizzas). If you wish, the 6-in-1s can be combined with herbs and other flavorings and cooked before using. In fact, Randy has a good recipe along those lines, using herbs and spices from Penzeys, one of the best sources for such items. For Randy's recipe, see Reply #2, at http://www.pizzamaking.com/forum/index.php/topic,74.msg484.html#msg484
What I have found to be a useful tip regarding fennel seeds is to grind them first in a mortar and pestle (or in a herb/spice blender). You get a lot more flavor out of them that way as opposed to using them whole. But you have to be careful not to overdo it. Ground fennel seeds can be quite potent. When in a hurry, I just crush the fennel seeds as best I can in by rubbing them hard against each other between my fingers. It's not as good as grinding them but still pretty good.