The Basis of Entering Paradise

Asalam Alaykom.What does it take to become a good Muslim (to enter paradise)? In some Hadith i read that the Prophet(saws) told people that they should pray, give zaka, believe in the oneness of God, fast in Ramadan and perform the Hajj and they would surely enter heaven.Now I also read some other Hadith that state that only 1 out of 100 people will enter paradise (yet in another it said 1 out of 1000) and that the Prophet would only enter paradise with only 70,000 or 700,000 of his umma(I'm not sure if those are meant who go in without trial but even the number of shaheeds should exceed that number). Somehow this made me think that it's nearly impossible to avoid the Hellfire.This brings me to another question. If I understand the Quran correctly once you enter Hell, you NEVER leave it. But some Hadith say that those who have done even one little good deed would be saved by some "interference".All these Hadith really confuse me, also another Hadith were Aisha(May Allah be pleased with her) made pillows with pictures on them. On this site I read that the Prophet didn't protest but on another site I read that he said that the one who made these picture would be punished in the hereafter. this brings me to my last question. Are plastic kits (miniature models of tanks and planes) haram?I apologize for mixing all these questions together but the mere fear of hell has left me somehow paralized for the past few days. I would be very thankful if you clarified and explained these questions and Hadith to me.Asalam Alaykom.