Convert software working on DOS to a Win7 new software

hi we have a program working in DOS and we need to convert it in a software installable on Windows7 (all win xp > compatible) i not have preferences in language of trascription but the software need to be visual (very similar or same) as the dos version we have all file and we will send you database and files architecture of original version. the program have a graphic interface in DOS and let user insert some data and print. program work offline. have only 4 database of people it's a "management". the file .exe work only if i use win xp with date 1994 otherwise not start program. after a lot of using the program ask a passkey i not have it and i want eliminate and bypass the request of this password. the new software need to create PDF and print version and print directly from program.