os commerce upgrade/repair

i have an oscommerce website using cre loaded (i dont know the version). It was hacked 3 years ago, i stopped using it because i was busy at that time. Now i'd like to upgrade to osc 2.3.x latest version. at the minimum - I'd like to keep the original template/layout before it was hacked - i'd like to keep the customers, the products database. - clean codes. unnecessary files/codes should be removed - I downloaded a back up after it was hacked so there are alot of files that were injected. I dont want any of these files/codes on the new one. - After you finish your work i'd like to check the front/back end on your server first. then i'd like you to upload all the files onto my server so I can check the individual file. Then I'd like you to upload to a server and activate the shop