Just because the windows is inside Linux, doesn't mean it won't get Viruses
That's like... having iron out in the rain. Would it rust any less with a silver plate under it?
I have tried Fedora's Red Hat, and I was rather disappointed. After that I installed Ubuntu, and I have fount that it's much better
If you are going to install Ubuntu, you might want to use
Easy Ubuntu, and try both Gnone and KDE environments to see which you like best.
As for NTFS support, well, as far as I know it's not 100% perfect, it can't quite write well on NTFS, but yes, Windows can easily support EXT3 though without the permissions, and it has caused me a certain "corruption" in the hard drive (which the Linux says is "uncontentious", but I believe it will be better in newer version (maybe even the current one, I installed mine a long time ago)