I was browsing through the Help files for blog inspiration, and came across a nice collection of the system variables that affect how you select objects.
They're grouped under the Selection Modes section of the Selection tab of the Options dialog, and nearly all of the system variable names begin with "pick". (So if you're having trouble "picking" objects, a.k.a. "selecting", it might be a good place to start next time.)
Noun/verb selection (PICKFIRST): When this is checked, you can select objects before you start a command. When it's not, starting a command forces you to select objects even if you had some selected before.
Use Shift to add to selection (PICKADD): When this is checked, you must hold down Shift in order to add objects to your selection set. If you don't, each click selects a new object or set of objects and de-selects whatever you had selected before. When this option is off, each selected object is cumulatively added to the selection set. You can hold down Shift and click on objects to remove them from the selection set.
Press and drag (PICKDRAG): When this is checked, you define selection windows by pressing-and-holding the left mouse button, moving the cursor to the other corner of your window, and releasing the mouse button. When it's not, you click once (and let go) to define the first corner, and click again to define the second corner.
Implied windowing (PICKAUTO): When this is checked, clicking in an empty part of the drawing automatically starts a selection window. When it's not, clicks that are not on an object have no effect. If you're in a command that has a "select objects" prompt, you must enter C or W to start a crossing or window selection. If you're not in a command, the only way to select objects is by clicking on them individually.
Object grouping and Associative hatch (PICKSTYLE): These two are sneaky, since they're actually part of the same system variable. If Object Grouping is on (PICKSTYLE = 1), selecting a single object in a group selects the whole group. If Associative Hatch is on (PICKSTYLE = 2), selecting a hatch object also selects its boundary object. This is different from regular hatch associativity, where modifying a hatch's boundary modifies the hatch -- PICKSTYLE is all about selection. If you want both Object Grouping and Associative Hatch turned on, you add their PICKSTYLE values, and set PICKSTYLE to 3.
There's one more Pick variable that's in another part of the Selection tab -- PICKBOX.
This one controls the size (in pixels) of the of the selection square. Anything inside or touching the pickbox square can be selected, so smaller pickboxes give you more control, and bigger ones give you more flexibility. The pickbox size can range from 0 to 50, but the default is 3.
If you set PICKBOX to 0, you're pretty much limited to selection windows, since it'd be impossible to click directly on an object.
Everything in this post is all about personal preference -- how you like to work. Nothing in here affects anything having do do with how you work with others. (Although in the "works well with others" area, there's a lot of potential for some CAD-related April Fool's jokes with these settings...but don't blame me if your coworkers don't appreciate the humor!)