NTFS is useful/necessary for large HDDs and/or files over 1GB. If you can easily reinstall your OS, go ahead and do so with NTFS.
As for Memtest, you can get a USB version, but it has to be loaded to the USB via Linux. Otherwise you'll need a burner (get a burner all ready!!
). You could buy a CD from them, but seems rather expensive. I suggest asking a friend nicely to burn one for you.
BTW, make sure your're looking on .com not .org. .Org is the older iteration of Memtest.