peace guys,
ALLAHU AL-KABEER (Most Great, The Supreme) or Allahu Akbar (Greatest) ??
as I know Allahu Akbar is not quranic word. is it
In Salat is there an action like to give selaam to right and left side 
I started to do salat 3 times a day. And it is 2 rakat in each salat. I say Chapter 1 and prostrate saying PRAISE TO BE GOD, GLORY BE TO GOD. at the end i say :PRAISE TO BE GOD who has not taken a son, nor does He have a partner in sovereignty, nor does He have an ally out of weakness. (all my salat takes 5-8 min max or less or more)
so guys , what do you think about it?? please correct me if i am wrong
(and i would like to know your salat doing if it is not secret) 
Your connection with God sounds good. If it works for you then take from Al Quran and recite it in your salat. For example; if you read something in Al Quran that you like, then say it in your salat.
Islamic claim:
'Allah' is simply the Arab word for 'God.'
Reality:
'God' in Arabic is translated 'ilah,' not 'Allah.'
Allah = الله (alif ا, lam ل, lam ل, ha ه)
ilah = اله (alif ا, lam ل, ha ه)
Islamic claim:
'Akbar' means 'great.'
Reality:
'Akbar' in English is translated 'greater,' not 'great.'
كبير (kebir) = Great
أكبر (Akbar) = Greater
'Allah' is not simply the Arabic word for 'God,' but the name of Islam's chosen deity and 'Akbar' does not mean 'great,' but 'greater.' Greater than what? The answer is - Allah is greater...than whatever god you happen to believe in.
As far as I am aware there is no action in Al Quran that speaks of doing salam to the angels.
Hope this helps.
Peace