I'd recommend that you play the game for a little while prior to installing any mods. That way you'll get familiar with the overall gameplay and you'll better appreciate what the mods bring to the table (i.e. more challenge, more historical authenticity etc).
I use TMO and RSRD myself but I know others prefer RFB and RSRD. With the JSGME software it is easy to switch in and out of those mods.
Have fun.
