The best sites I can find are the OV guide www.ovguide.com/movies_tv/anastasia.htm, this is an excellent site that does not force you to download anything on to your computer and it also suggests a number of sites you can find the movie to watch.
Megavideo www.megavideo.com/ is one of the most popular streaming videos online, the only issue with them is they have a cut-off point after 75 minutes so you have to wait half an hour in order to continue watching your film or you need to sign up to membership which incurs a monthly charge. There is really no need to pay just treat the interruption as a toilet and snack break.
If you cannot cope with the interruption then the site Let Me Watch This www.letmewatchthis.ch/ houses a few more alternatives. It can be a bit hit and miss with the quality but in the list of streaming choices aim for DIVX or Loombo, although you will need to download software for DIVX but the quality is second to none and gives no constant updating or management grief.
Blinkx www.blinkx.com/ is also a very reliable source for films and a very safe site to use. Surf the channel www.surfthechannel.com/ has an exhaustive list of children’s films as well as Anastasia.
The final recommendation is Watch Movies www.watch-movies.net.in/ yet another regularly updated list along with a substantial archive of films.