This is the key question. Do you plan to rebuild the engine on your SUV? Or maybe just change an O-ring on your backpacking stove? Different tasks may require very different tools. So first figure out what it is you plan to use these tools for?

Regarding what to keep them in, again it depends. At home I have two tool boxes on my work bench in my garage. One is a 2 drawer Craftsman mechanics tool box with my mechanical tools in it. Another Craftsman tool box has most of my carpentry tools. A few of the most frequently used items such as screwdrivers, pliers, crescent wrenches, etc are hanging on the peg board above the workbench.

However on my boat I find a tool bag works better. Boats usually are cramped for storage space, and those storage spaces are often very oddly shaped. A tool bag seems to fit most easily there. Also, the tools don't rattle so much as the boat rocks and rolls.

While generally I agree that one should buy quality tools, there are cases when cheaper "beater" tools might be the best choice. So in my cars I keep a small selection of not so expensive tools. Given the complexity of newer vehicles, I don't expect to be doing any major roadside repairs. A few simple cheap tools are adequate for most things I might do along the road. If someone breaks into my car and takes the tools, it is far less painful if it is a bunch of cheaper tools (worth a few 10's of $$) rather than a nice set of high quality Craftsman tools worth hundreds of dollars.