First, many apologies to Royal, but I don't expect her to win tomorrow. If she does turn out to be the victorious party, well, kudos for her.
Second, a caveat. Much of what he will be able to do will depend on the outcome of parliamentary elections in June. If his party does not control the parliament following those elections (if France has a period of political "cohabitation"), he'll have to deal will a legislative body hostile to many of his proposals.
So what's on Sarkozy's agenda? What is he ready to serve up?
Economy: Tax cuts and labor market reform will be a theme of his administration. Sarkozy likely isn't a secret libertarian at heart but he will be (IMHO) the most pro-market President France has elected during the Fifth Republic (when French Presidents really started to matter in the French political scheme).
Foreign Policy: I expect to see generally warm relations with the U.S. from his administration. I also think that he's generally in favor of the E.U. I don't expect to see him involve French forces in Iraq.