According to almost every source known to man... The episode "No meals on wheels" is on season 5. All episode guides say that season 5 has 18 episodes, but they only seem to have put 14 on. Why would they hold back on producing every episode? Especially considering that said episode is quite possibly the best FG episode in the universe. Someone explain please.
The DVD releases are a bit confusing. The Family Guy Season 5 DVD actually contains episodes from season 4. The newly released Family Guy Season 6 however does contain the first 13 episodes from what is actually Season 5. There are a further 5 episodes in season 5 (including No Meals On Wheels) which will no doubt be released on DVD as Family Guy Season 7 (along with the first half of what is actually Season 6). Confused? I don't blame you. Basically all the Family Guy episodes are coming out on DVD in order, but the DVD titles of "Season X" bear no relation to how the episodes fit into Fox's season format for the show.