As-Salam Alaykum dear sister,
You have brought up two issues:
1) The marriage of Prophet Muhammad [s] to Aisha [ra]. The best article I've seen on this topic is available can be accessed by emailing
The Religion of Islam - Home Page ...just email them and ask them "why did Prophet Muhammad [s] marry Aisha [ra] when she was such a young age?" You can contact them here, and they'll email you the article in one day:
The Religion of Islam - Contact Us
Or I can email it to you myself. PM me if you want me to do that. It will insha-Allah end all your doubts on the matter.
2) The second issue is the matter of when hadeeth were written. This is actually a lie propagated by the internet cult known as the "Quraniyyoon". It is completely false to say that the hadeeth were only written down 200 years after the Prophet's death. Rather, the hadeeth were written down much sooner than that.
The reason that the ICHRT (internet cult of hadeeth rejector teenagers) reached this erroneous conclusion was that they looked at each famous compilation we use today, such as Bukhari, Muslim, etc, and they realized "wow, these are all written way after the Prophet [s] died"....and then--because they lack in any real knowledge or formal education--they began making websites and preaching their lies as if these were based on fact...
What these teenagers did not realize was that there were other compilations that were made RIGHT after the Prophet's death -- not 200 years afterwards. It's just that these compilations are no longer as popular as Bukhari, Muslim, etc...
The reason these early compilations are not as popular is that the early compilations were scattered...furthermore, the later compilations by Bukhari/Muslim were heavily authenticated by the scholars.
You can read an in-depth refutation here:
http://www.call-to-monotheism.com/re...re_unreliable_