Calling all interior designers

Hey

I can't decide whether to get curtains or blinds for my living room/TV room. The room I think is 5m x 4m (small English house)

Also we have a radiator under the window and can't move it. I really wanted light filtering roman blinds and full length curtains, but don't think can have full length cause of the radiator. Can I? My husband says it'll make the room smaller.

Need suggestions what to do? I don't like shutters. And the window is 80 inches wide if it helps xx