In terms of "formatted for windows" what do you mean (FAT? FAT32? NTFS v1? NTFS v2? NTFS v3? NTFS v3.1? NTFS v3.1 with transations and symlinks?)
What do you plan to do with the data in the first place? If it is mainly movies/media, are you planning on wanting to share it with other computers on your network or view it from the now linux system? Another question to consider is "were the TV shows recorded from the windows system through media center and as such possibly DRM'ed to only be viewable from that system and/or associated media extenders"?
Most versions of windows based filesystems can be easily mounted and read from a linux distribution (you simply need NTFS-3G installed on your linux box; some distributions come with it, but notably Redhat and derivatives (CentOS, Oracle Linux, Scientific Linux, etc) does not and you would need to install it). Writing to those filesystems can be tricky depending on exactly what it is (FAT and FAT32 have no problems, and for the most part, NTFS filesystems made on systems up to XP have no issues, but Vista and forward might have issues from time to time resulting in possible data corruption).
If you simply want to put all those drives in read-only mode you will have no problems viewing and sharing the storage to other systems on your network. If you want to use them for active remote storage from other systems, you might have issues. At which point I would say you should copy the contents out and reformat to FAT32 or ext3. Only reason not to use FAT32 would be if you need files that are larger than 4GB (which could easily be the case if you have HD video content). Ext3 is the next best choice, as there are now drivers you can install on windows systems in case you need to connect it back to a windows box for some reason (which you shouldn't need to, but it is nice to have in case of system failure and you have a desperate need to access data from one of the drives).