This is the 2647th most frequent Russian word.
фильмов
The Russian word "фильмов" is the genitive plural form of "фильм," meaning "of films" or "of movies" in English.
In this sentence, 'фильмов' is the genitive plural form of 'фильм' (movie), used because the preceding word 'много' (many) requires the genitive case.
Я люблю смотреть много интересных фильмов.
I love watching many interesting movies.
Here, 'фильмов' again is in the genitive plural case, used because it qualifies the noun 'коллекция' (collection), which is the subject of the sentence.
Коллекция старых фильмов очень ценна.
The collection of old movies is very valuable.
In this context, 'фильмов' appears in genitive plural, determined by the word 'несколько' (several) which also governs the genitive case.