Selection in the DV lottery does not insure that you will receive a green card. Since not just one individual may be admitted on one lottery selection, there are more individuals selected than are visas ultimately available.

In order to adjust status, you must be in status; in the case of H1B, you must be properly working. If you have any "issues" with your stay in the US (such as periods where you were out of status or illegally present but did not accumulate a ban), you need to speak with an attorney to determine the potential effects on your green card.