sentences grammatically acceptable or not

Hi!
I need some help...Are these sentences grammatically acceptable?

a) I am not used to have to say not
b) I'd be careful who you said that to
c) I was amazed by the fact that Peter should arrive late
d) Peter was sure that Penny should finish the project on time
e) They were cruel doing such a thing
f) He was uncertain where to park his car
g) He is hopeless at to fix things
h) That film was fascinating to watch
i) They were indignant that happened
j) They were insistent that all details should be specified in the contract

In my opinion, I would change:

a) I am not used to having to say no

d) Peter was sure that Penny finished the project on time 

g) He is hopeless at fixing things

f) and h) are ok for me

What do you think?

Hi guys,

I added a few comments to Paco's version, in pink.

a) I am not used to having to say not. [I agree with you.] More natural is 'I am not used to having to say no'. Why would you say 'not'?
b) I'd be careful (who)/whom you said that to. [I rather choose"whom"]More natural is 'I'd be careful who I said that to'
c) I was amazed by/at the fact that Peter should arrive late. [by and at are both OK] OK but very formal. More natural is '...Peter arrived late'
d) Peter was sure that Penny would finish the project on time. [I think it should be future-in-past]
e) They were cruel doing/(to do) such a thing. [doing and to do are both OK] 'To do' is the more natural
f) He was uncertain where to park his car. OK
g) He is hopeless at fixing things.[I agree with you]
h) That film was fascinating to watch. OK
i) They were indignant about/at/over what happened. [indignant that happened?] indignant about/at/over what happened sounds OK
j) They were insistent that all details should be specified in the contract. OK
More natural is '... all the details ...'

Best wishes, Clive