extreme behavior 2 yr old

My grandson is 2 yrs old (4-6-08)
When he was 3 mos old he had viral menigitis (meningitis). He has had a very violent temper since he was 1 . His teeth development has been different. He finally cut a tooth when he was 16 months old and he is still cuting teeth. He has an older brother who is 4 and I never have seen this kind of behavior in him. The 2 yr old will be playing fine one moment and then the next he is very upset and nothing has been done to set him off. He will hit mom, dad or anyone around. He will throw things and nothing seems to console him. I would think that it might just be a home situation but he is behaving the same at daycare. Mom is very good about telling him why he's in trouble and she sends him to his room and he comes out she puts him back. He is spanked not hard just enough to get his attention. A swat on the bottom and told that the way is behaving is not acceptable and that if he does not stop he will be sent to his room . Ten times out of ten he continues and is sent to his room until he can behave better.
When he is happy he is a wonderfull loving sweetie but we just don't know what to do when he's bad.
When mom picks him and brother up from daycare he does not want to hold her hand and walk to the car he will run into traffic so she has to hold him in front of her faceing out so he cant hit her. What can we do?

[RockRose]

Is there a way he won't have to be sent to daycare all day and then be picked up by a parent at the end of his day?  

As a country,  we are ignoring the fact that many of  our children are being ruined by daycare.   This generation and last generation of children have unprecedented use of antipsychotics and antidepressants and ADHD medications.  

Preschoolers are being put on drugs at an alarming rate.

Is there any way that you,  Grandma,  or his actual parents can parent him instead of an employee?