for me personally, I dont think I would have been better off knowing my grandparents!
my dads father committed suicide, the year after I was born. He had remarried and had 2 children to another woman, my dads sisters (there are 5 of them) were concerned that he may have been sexually molesting the daughter as he had with all of them, so they all decided to take him to court, he took the cowards way out.
My nana, dads mum, is a bit loopy, always has been aparantley, she wouldnt know who I was if she fell over me (she didnt even know who her own son was, he tried to give her a lift one day and she freaked out!). After hearing quite a bit about how my father grew up, Im actually glad that neither were a part of my life.

My mums father was an alcoholic, who divorced my grandmother in the 70's, and shacked up with one of his "floozies" ( I always thought that was funny, as to me she was that old, she was ancient!!) only ever saw him at xmas and easter, he died when I was 14, I always regret not having made more of an effort to get to know him, as he lived just down the road from us, but he was always at the pub anyway.

my mums mum, grandma, is still around, she is a dear, I love her to bits, but she is a bit loopy too. There is bad blood in the family towards her and I still carry a little guilt (even though I know I shouldnt ) about it, her second husband was a bit of a pedophile, he had parkinsons disease and would always "accidently" fall on top of me or (girl) cousins and then start humping us, we always thought it was funny until we grew up and were told the truth many years later.
anyway, his nephew had just been released from prison for rape or some thing similar and was staying at their house, mum desperately needed someone to look after me (I was 2) after being assured by my GMA that HE wasnt there, she left me there, when I was picked up I told mum about how "ricky" put his hands in my knickers, and told me not to tell anyone....
needless to say no one spoke to my GMa for years, some of my aunties and uncles still dont. She only lives around the corner from my mums place, and now that the 2nd husband is dead, I do acyually try to make an effort with her, man, she has some interesting things to say!

so, yeah, sorry for the ramble, but, like I said for me, not a biggie!

My parents are a big part of Js life, sadly the same cant be said for DPs parents, his father is ATM living in a commune in the phillipines, he is a big hippie and doesnt really believe in "emotional" attacthments...
His mother has BIPolar and everything is always about her, we try to see as little of her as possible, due to her drug addict, abusive boyfriend, and their attitudes to life, not something I want J exposed to. In the 18 months since we had J, she has been to our place once, the other 2 (!) times she has seen him, we were somewhere else she was at the same time. oh well.