gra,
congratilations with your IL! As to documents, most people say you will need FOR SURE originals of birth certificate and marriage certificate (and passport and DL of course). Also, they ask for your EAD, or H-1 approval (original) if you do not have EAD. Other documents they may even not ask. I collected most of my previous visa documents, but could not find all, I hope if I have previous H-1 approvals they will not ask for receipts

They also may ask for taxes (or may not, as happened recently with my friend), and you may get IRS tax transcripts, but I think your copy of tax filings would work also...
I will update my interview experience soon...