Once again we have the silly Simpsons style construction, where the events in Act 1 randomly kick off the main plot.  This is such a convention of animated shows that it never strikes the audience as odd, even though it really is.  From the perspective of dramatic narrative, you're supposed to start with, you know, the story.  Not a throwaway little pre-story that ends when it nudges the actual story into action, and is never referenced again.

Anyway, where was I?  Oh yes, there's a sale at the DVD store, "because DVDs are outdated, just like white track stars."  (I'm not actually sure what DVDs are being replaced in favor of, although maybe that's a silly question, given that I watched this episode on Hulu.)  Every DVD is only a dollar!  

Peter is overjoyed to discover the last available copy of "Roadhouse."  As well he should be, because that movie is AWESOME.  I laughed when the clerk tried to add a free copy of Robin Williams' "What Dreams May Come," an offer which Peter refuses in no uncertain terms.  "if that DVD even touches Roadhouse, I will kill you."  

Operating under the influence of Patrick Swayze, Peter runs around kicking people and then turning to the camera and saying "Roadhouse."  (The show referenced this joke again a few episodes later in "Business Guy.")

After Peter gets into a car accident while driving Roadhouse-style, Brian makes a date with a beautiful 21 year old girl.  But she flakes out on him, so he starts dating her mom instead.  Rita claims to be 50, although her age would more likely be 55 or 56 judging by Brian's comment that the flag was "missing a few stars."

Everything proceeds fairly predictably from this point on.  Has there ever been a successful plot revolving around Brian's romantic liaisons?  The family gives Brian grief for dating an older woman, Brian gives an impassioned speech in defense of older women, but later he gives into his baser urges and has sex with a bar slut while running an errand for Rita.  When he confesses, Rita dumps him, thus neatly getting the script out of the corner it had painted itself into.

This episode is full of wasted potential, from Peter's brief Patrick Swayze obsession to Brian's uncredited cameo in "Die Hard."  And a particularly odd gag in which Stewie dreams of playing water sports with Shia LeBeouf. ("That's right, Shia, gimme all you've got!")

Everything about "Brian's Got A Brand New Bag" is thoroughly predictable, including Lois' reaction to the news that Brian's girlfriend is "mature."  Which is a little surprising, if you think about it, because Lois is no spring chicken herself.  If she was 18 in the episode where Peter travels back in time to 1984, then… well, unfortunately you have to do the math by our real life time, in which case Stewie is ready for fourth grade.  

But you get the picture, she's in her 40s.  Hardly in a position to throw stones, and although that is Lois' role with relation to Brian's girlfriends, it worked a lot better when she was making fun of Jillian for being stupid and too young for him.