Terrible twos already?

Help!

We're getting awfully close to those terrible twos and some rebellion, independence, and boundary testing are already setting in. I can't believe how frustrated I'm getting already knowing that this is only the beginning. 

Most of the time Drew really is a good kid.... but these are some of the things that have been irking me lately:

• refusal to come when asked and stubbornness in doing/complying with simple tasks (like tooth brushing or diaper changes)
• collapsing when I pick him up to do what I asked (yes, melting cat style). This is already a strain on me physically and I can only imagine as the belly grows.
• pretending to hit me when angry with me. He doesn't actually hit me, though part of that might be my own quick reflexes, but most of the time it's an "air threat"- he limply throws his arm in the air towards me.
• kicking me during diaper changes. Not hard kicks, but "point being made" presses against my chest and belly. This is particularly difficult because it tends to be a game with Jason and Drew, but when done with me the tight-lipped, rebellious face says it is not for fun. With a growing belly this is absolutely not acceptable. I've asked Jason to stop the "game", and he has, but what makes this particularly difficult is the fact that we're in the middle of a diaper change and all I want to do is get a diaper on his bottom instead of being interrupted to deal with discipline. Naked bottom time-out?
• a LOT of temper tantrums. Most revolve around having to leave his blankie in his crib when he wakes up or not getting to watch Elmo. Others revolve around not getting a food or toy he wants. (No, we don't give in to the temper tantrums, but sometimes I wonder if that adds to their intensity because he KNOWS he's not going to get what he wants and he is truly that disappointed).

Case in point: yesterday Drew did not want to wait
for the pizza to cook

I can only imagine I'm going to get slaughtered in one direction or another with my following statements, but these are basically my current discipline beliefs:

1. I am not morally opposed to spanking. My sister and I were spanked occasionally growing up and I believe it did us no harm, and in fact probably did us some good. We were only spanked on very rare occasions (my mom tells me it may have been only 2 or 3 times total), and I cannot even remember the specifics of those occasions. We have grown into respectable, responsible, non-violent women.
2. I currently believe, however, that Drew is too young to be spanked. His mind can't currently comprehend the difference between a punishment and hitting out of anger. This belief was solidified recently when I witnessed a toddler hit his baby brother, to which the mother responded by hitting the toddler, to which the toddler responded by hitting the mother back (what does the mother do at that point? In this case she did nothing). Not a good cycle. If I want to teach him not to hit others, especially me, then how can I teach him that when I'm hitting him? (And if that is my belief, is spanking really ever okay?)
3. If spanking is used as a punishment, I believe it needs to be done separate from the punishable action, ie. the parent is not responding in anger. I think the offense and punishment need to be explained to the child. At this age, I believe Drew is too young both for understanding a detailed explanation of a punishment, as well as for connecting a punishment that is separated from the offending action by more than a few moments. If he refuses to listen to me this morning, I can't expect him to make the proper connection if I give him a punishment tonight. I think discipline needs to be fairly immediate at this age.
4. We are currently working with time-outs, but they don't seem to have a strong effect. Having plenty of child-care experience, from babysitting to nannying to working in a daycare to teaching elementary-age students, I have been around enough to feel time-outs really are ineffective.

My first issue with time-outs is he does not get the concept of "sit there until I tell you that you can move" (or even "sit there until this timer goes off, or until all the glitter in this jar settles). Nor does he get the concept of "if you move, I'm adding another minute to your time out" as he has no concept of time. Therefore time-outs are conducted by him sitting facing a blank wall and me standing with my back to him, the back of my legs holding him in place. I count to 90 (a minute for every year of age- in this case a year and a half), sometimes out loud, sometimes silently.

Second, as time goes on, he seems more and more unfazed by the time-outs (my general complaint with time-outs in general). He used to cry, or at least look pouty when put in time out. Now he sits there and simply tries to peer up at me, or find something on the floor to play with. He also frequently immediately returns to the offending action (this has resulted in repeated time outs one after the other, which also seem ineffective).

I feel powerless sometimes to get him to cooperate. I simply want to teach him to respect us and to listen to what we say. I want to teach him that we will not repeat ourselves 5 million times, or even 5 times, before an expected action is completed (or a behavior is stopped). Maybe it's too early to worry so much, but I also feel this is the age when he's learning exactly where his boundaries are. How do I teach him those boundaries right now if one punishment is too severe and the other ineffective?

I know tones and looks can have a powerful effect, but when a certain stubbornness sets in no mom-look or voice seems to get the point across.

Some small things I do that I *think* work... when I do ask him to come, if he doesn't come I tell him "Drew, I asked you to come" (with that special tone and arched eyebrow) and give only a few seconds before I get up and get him myself. In other words, I don't allow my own laziness stop me from making sure he fulfills the requested task. Along similar lines I physically walk him through requested tasks such as tooth brushing (making him hold the brush himself when he refuses to sit still or open his mouth for me) or picking up the dog food that he spread piece by piece across the floor (I know he understood the concept of cleaning it up because he happily picked up a few pieces, just simply refused to do the rest- and, in this case, he was not being punished for putting the food on the floor, I simply asked him to help clean it up and expected follow-through).

Does anyone have any suggested tactics? A better way to make time-out work? Something other than time-outs? Thoughts on spanking?