College discover card and master card maxed out. Remove fix clean delete late payments raise credit score

In college i was given a discover and Mastercard that i maxed out and eventually had serveral late payments. After graduating I was able to pay off both of the cards. During college i closed both of the cards, thinking that it would help me. In 2006 my credit report showed that both cards were paid in full. I thought that i needed to establish good credit by getting a new credit card. The only company that approved me was capital one. I have been paying all of my bills ontime, but my credit still lingers around 640. What should i do to increase my credit. Currently i have a balance on my capital one card. Also, is there anything that i could do to have the late payments removed from my credit report -i.e. discover and mastercard? Should i open the discover card account - which is my oldest account - and have my balance transfered from capital one? Please help! Also, I have amortgage and two other credit cards open which are in good standing. My goal is to hopefully have a minimum credit score of 750 in the near future
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if you had late payments and paid something off before negotiating you cannot help your report.
Unless
I re open one of those same accounts, pay good 1 year, then ask for removal of old lates.

get 3 open rated accounts with no past lates, drop balances on credit limits to less than 80% of maximum.

shoot for 700-720