Hi there mindyspears,

Right of admission to the United Kingdom

11.
(1) An EEA national must be admitted to the United Kingdom if he produces on arrival a valid national identity card or passport issued by an EEA State.

(2) A person who is not an EEA national must be admitted to the United Kingdom if he is a family member of an EEA national, a family member who has retained the right of residence or a person with a permanent right of residence under regulation 15 and produces on arrival—
(a)a valid passport; and .
(b)an EEA family permit, a residence card or a permanent residence card. .

(3) An immigration officer may not place a stamp in the passport of a person admitted to the United Kingdom under this regulation who is not an EEA national if the person produces a residence card or permanent residence card.

(4) Before an immigration officer refuses admission to the United Kingdom to a person under this regulation because the person does not produce on arrival a document mentioned in paragraph (1) or (2), the immigration officer must give the person every reasonable opportunity to obtain the document or have it brought to him within a reasonable period of time or to prove by other means that he is—
(a)an EEA national; .
(b)a family member of an EEA national with a right to accompany that national or join him in the United Kingdom; or .
(c)a family member who has retained the right of residence or a person with a permanent right of residence under regulation 15. .

(5) But this regulation is subject to regulations 19(1) and (2).
Source here at The Immigration (European Economic Area) Regulations 2006

Addionally, if you are travelling with your EEA spouse you can join the EU queue at UK arrival.
Travelling alone then technically you should join the Non-EU queue.
You do not need to fill out a landing card at UK arrival.

Hope that answers your questions