Can the post decision activities of I-130 petition be completed while in USA on visitor visa.

She can adjust her status here in the United States once the I-130 is approved.

I agree with my colleagues. You can do all these things but you cannot be employed by your LLC.

How is my case relaterd to USA

You may have a legal case but this is not an immigration question.

Can I apply for a waiver now? What are my chances of success

It really depends on how you exceptional your hardship truly is. Speak to an attorney.

Change of status from J1 intern to another J1 category in US like work and travel or trainee?

Any change in J1 category must be consistent with the original exchange objectives. Speak to your responsible officer.

Will they let my spouse in? (I am on H1-B and my spouse in on B1/B2)

She should enter the country with an H4 visa.

My H1-B got approved and my spouse is on B1/B2 , can I bring her back with me on the sane visa or should I change her visa to H4

It is better for her to enter the US as an H4, rather than changing status here.

Can I get my alien wife a green card while I am still working abroad ?

It depends on whether you are a US citizen or not. If you are green card holder, you may have abandoned your residency.

Do I have to list all my traffic citations? speeding etc... on my citizenship application? If so, how far?

It is not necessary to list them unless you would like to.

Worked on H1B for 5y 6m 27dy. I have 5m 3dy remaining. Inorder to reset my H1B should i step outside US for 1y or just 6m 27d

You need to leave the Us for o e year unless you have another application pending, such as Perm certification.