To be honest (and not in a rude way) trying to use the same colours as vista is always going to be hard the site its self seems very empty and the type of site i would exit striaght away, i believe that any one could have done this site i.e. its nothing special sorry!
ways to improve:
you can improve your site by removing the sounds on your buttons adding a lot more content rather than now because it looks like a affiliate site that will sell email addresses which is not good!
the site all in all looks like a hour job that was never finished try instead of rounded edges going for a more classic look and box it all in, also like others have said and i said you need to make the site about free offers and then add in a differant page the option to select and add their email address. just space your work out over 3-4 pages to give your users something to look at!
thats about it for now as i dont have much time i hope you take this as constructive information and not just me being rude
hope it all helps