有点儿(original form is 有一点儿)means: have a little bit... which is a verb. Can be followed by adj. adv. noun.
Eg: 我有一点儿冷。(I feel little bit cold. Followed by adj.)
这车有一点儿慢。(This car is little bit slow. Followed by adv.)
那家店有一点儿存货,你要吗?( That shop has some left over goods, do you want them? Followed by noun.)
一点儿 means: a little. ( "一" is optional, can just use 点儿 as well.)
which is 1. adj. to modify noun. 2. adv. follow adj.or adv. means comparative.
Eg: 1. 我们还剩一点儿时间.( We still have some time left. Followed by noun.)
你再盛一点儿汤.( Please get some more soup. Followed by noun.)
2.你有小一点儿的鞋吗? ( Do you have smaller shoes? Follow SMALL and change it to SMALLER)
我今天好一点儿. ( I feel better today. Follow GOOD and change it to BETTER)
This is one way to express comparative. Very useful.