What to do in this situation? Should I tick "yes"? What impact will have the mere arrest on my visa application? I am very anxio

Yes you will need to answer that you had an arrest and be prepared to provide certified copies of the records.

Who is a LPR and what is the difference of a citizen

An LPR is a lawful resident of the US and is not a citizen. The spouse of a US citizen may adjust in the US even if out of status. The spouse of a...

Recommend you renew your resident card as it is possible for SSA to suspend without adequate proof of eligible status.

What is sponsor requirements to fill the I-864?

See the instruction for form I-864 for qualifying income for spouse. If not eligible you may need a co sponsor.

Which Visa Subclass to Apply for at least 1 Year Stay with Work Allowed.

Either E1 or possible E2 are appropriate as my colleagues have noted.

Can i file H1b without opt? Does it require client letter?

OPT is not required for H-1B eligibility as my colleagues have noted.

If my son has been charged with dui misdemeanors Infraction. Would I still get my USA visa or they will deny me cos of my son.

As my colleagues have noted your son's dui should have no impact on your visa eleigibility

Can my employer B again extend my H1b visa for 3 more years with the employer A I-140?

Yes as my colleagues have noted with an approved I-140 your second employer may extend the H-1B

My question is, can I (as a born US citizen) sponsor my older sister in law and her 12 year old daughter?

Your parents in law may petition when they become US residents and your husband may petition for his sister when he becomes a US citizen or...

How can I get i-485visa if I have a B1/B2 visa?

When your daughter becomes a US citizen she may petition for you.