Hi, I have few questions like to ask.

1) why applying for citizenship, do they only go back to last seven years of criminal history or there is no limits ?
2) if you got arrested and didn't serve any jail time and you paid your fine and restitution, are you still eligible to apply for citizenship ?
3) Felony means you server jail sentence ? I guess what im trying to ask here is, if the sentence was probation and pay restitution, does that disqualify me to apply for citizenship ?
4) If I still on probation, can I renew my permanent resident green card ? any chance I could be deported ?