I would recommend the Condo Parque,
www.condo-parque.ch.vu. It has a great location right in the Colonial District across a block south of the entrance to Calle Conde. It has a bar on site as well which is popular with the expat community, so there will be lots of Dutch, US, Canadian, etc. there. It is by no means a nightclub atmosphere! Just a quiet bar in the lobby. Probably only around $30 a night. There are pictures on their website, and it sounds like just what you're looking for. The location can't be beat!