1. Pay down credit cards to about 35% of their credit lines. DON'T pay them off completely or close them out. The length of time your accounts are open helps your score
The trigger for balances in relation to credit limits is too high on revolving accounts is 30%
Yes dispute all derogatory open credit with all 3 credit bureau's.
But, to answer your question I would need more information. If your wife can debt ratio on her own you may get a better rate.
Your employment... Self Employed? If so 2 years tax returns and they use your profit and may add some deductions back for qualifying purposes Full Documentation which is the best rates.
Right now I feel if you are self employed your best option is a Bank Statement program using your deposit totals for 6 mo, 12 mo, or 24 mo. (The longer the better your rate will be)
So if you want try to give some income information. Then I can try to give better advise. PM it if you would rather not make it public.