If you want a legit site for downloading ROMs, go to Emuparadise or Romulation (if searching for Wii ROMS). This site will often install programs without knowledge: I have once downloaded Sonic 1 and it installed "CoolROM Downloader" without my knowledge then changed my main page into "CoolROM safefinder," which fills up my entire cache and had to restore Firefox to it's original state in order to get rid of it.
The FAQ clearly says "Our downloader is an executable program that makes your download process much faster (by directly downloading the file and accelerating download speed) and ensures the file is virus-free," but in reality it in fact installs viruses on the computer, and the only way to download it without the downloader is the alternate download with ads and file timing.
The alternate download is also the download before they replaced it with the scammy downloader, with extra ads and file timing. It is not recommended for classic console fans, however, forgetting the irritating download, the quality of the ROMs is very good.