It really depends on your tastes in RPG's.
Dragon Age: Origins is more focused on the Traditional aspect of WRPG's, much more in the likes of Baldur's Gate, Neverwinter Nights, Icewind Dale and such. It's a really tactical RPG which has lots of micromanagement and AI plotting in order to succed.
Demon's souls is not your average RPG. It really doesn't fit into either the JRPG or WRPG category, as it takes a bit from both, imo. It's a very hard RPG, with a disturbingly steep learning curve, so the initial frustration can drive you away if you don't have patience and persistance required for it.
It's also one of the best RPG's ever made, it's extremely well balanced and no death is ever cheap, since the game gives you plenty of chances to survive, as long as you have the skills required for it. Also, it's story is very muted, as it happens along the game, so you'll have to keep a very keen attention to every small detail and NPC dialogue in order to understand the game world.
Current PC Build
CPU - i7 8700K 3.7 GHz (4.7 GHz turbo) 6 cores OC'd to 5.2 GHz with Watercooling (Hydro Series H110i) | MB - Gigabyte Z370 HD3P ATX | Gigabyte GTX 1080ti Gaming OC BLACK 11G (1657 MHz Boost Core / 11010 MHz Memory) | RAM - Corsair DIMM 32GB DDR4, 2400 MHz | PSU - Corsair CX650M (80+ Bronze) 650W | Audio - Asus Essence STX II 7.1 | Monitor - Samsung U28E590D 4K UHD, Freesync, 1 ms, 60 Hz, 28"
