If you get a recent model and it's a 64 bit machine it will have a real Windows 7 OS installed. Right now, personally I think you get the best bang for your money w/ ASUS. If you go over ~$600 and get a real laptop & not a netbook they come w/ Windows 7 home premium.
Check 'em out on amazon.com (you don't have to buy from them), and see if you want to return the Samsung.
http://www.amazon.com/s/qid=1283474093/ref=sr_st?keywords=ASUS&page=1&rh=n:172282,n:!493964,n:541966,n:565108,k:ASUS,p_36:2421888011,p_n_operating_system_browse-bin:2287320011,p_n_size_browse-bin:2242799011|2242800011,p_4:Asus&bbn=565108&sort=price
ON EDIT: There are even 3 models well UNDER $600 that run Windows 7 premium--two ultralights if portability & good battery life is important to you (ASUS UL20A-A1 & ASUS UL30A-X5) and one w/ a larger screen if it will mostly stay home (Asus K50IJ-X3). http://www.amazon.com/gp/search/ref=sr_nr_p_36_0?bbn=565108&keywords=ASUS&sort=price&qid=1283474859&rh=n:172282,n:!493964,n:541966,n:565108,k:ASUS,p_36:2421888011,p_n_operating_system_browse-bin:2287320011,p_n_size_browse-bin:2242799011|2242800011,p_4:Asus&rnid=2421885011&low-price=500&high-price=600&x=14&y=10