[dekeguy]

Blue Lodge would not cause any heartburn. Its a generally accepted term.
Constituent Lodges might be better than subordinate lodges but not a biggie.
I don't think anyone would get bent out of shape by any thing you said as it would be obvious you are politely inquiring about rental and expressing general interest in the organization.
You might want to check on their policies regarding what is allowed and what is not. Some jurisdictions prohibit alcohol anywhere in the building. Some don't have a problem with it in social rooms. Some don't rent to non-masonic bodies. Some require sponsorship by a mason. Some have few if any restrictions other than to keep the building in good order. Each Grand Lodge is an independent authority and rules its own domain. Blue Lodge Ritual is exceptionally similar in all jurisdictions in the USA (except for Louisiana where there are a few lodges which operate under old European working rituals) but house rules vary widely.