I went to college for Early chlildhood education-definitely normal behavior. He is starting to show his indendence and trying to show some control over his situations, testing his limits. Unfortuantely, it is through throwing, hitting etc. It is hard for them to put their wants and needs into words which frustrates them, causing the outburst. Help build his vocab by continously verbalizing his feelings (I see it makes you mad when your tower falls over)so he can start to learn what to say.
When he acts out inappropriately, move him to another situation. If he throws blocks, tell him he can't play with blocks because they are not for throwing and move him to a different toy. If he's sitting on your lap and hits, tell him he can't sit with you if he is hitting. Explain everything to him and redirect. A time out at this age is not necessarily effective.
Get involved with a local mom's club or MOPS group to be around other children. Gymboree is great too but pricey. At around 2 years, they do what is called parallel play (playing side by side children while not directly interacting). The children learn by watching how others play and act socially. This type of play sets the child up for the next stages of play, pretend play (age 3)and collaborative play (age 4).
Signing him up for day care will only increase the problem. First, by separating you two and taking him out of a loving, home environment. Secondly, the behavior of children in full-time daycare often sways to the negative side. Imagine 12 1-2 year olds fighting, hitting, tantrums, etc. Not too mention the exposure to biting and all the other illnesses that float around.
It is a rough stage that will pass. Watch for the molars too, maybe try some oragel or tylenol to see if that helps his mood, then you will know it's teething.
Good luck and be patient.