Well, there have been, like, millions of McDonalds ads, of course. Probably many of them I wouldn't remember or care about, but some are memorable... even if I don't remember them until I see them on YouTube. But I'll try to put at least a few here, starting with some featuring Ronald and his friends, from like the early 80s to the early 90s. There are probably lots that I can't find. (Like I remember once Ronald was talking on the phone and kept saying "You don't say." Finally he hung up and someone asked who it was, and Ronald replied, "They didn't say." Shame I can't find that.)
But here's one from the 80s with Birdie learning to fly, and "there's something terrible on TV", and one from the 90s with Ronald getting a new hairdo. There's a brief Halloween one featuring the McNuggets in a haunted castle, which I've always liked (probably from the early 90s). There's a classic from the 80s of Ronald and some ice skating kids. Then... for awhile in the 80s there was a series of "Mac Tonight" ads, featuring a piano-playing guy with a crescent moon for a head. Very weird. I'm including a compilation of some of his ads, though I think you'll have to watch it directly on YouTube rather than on this page. Then there's an ad with the Big Mac ingredients song. Then one about a girl doing a piano recital. And one about some young girls at Camp Nippersink (I always think of that one as "quack quack waddle waddle"). Then one with kids getting through their first day of high school. Then "Big Dreams" (which I always think of as "electroencephalographic technologist"). Then a series of three ads from the early 90s, featuring a teenager named Calvin who got a job at McDonald's. Then one from the mid-2000s featuring a couple of hipsters who are happy that McDonalds has coffee. Then one with a kid eating his happy meal funky-style. Then a totally awesome "Archenemies" ad from 2015 (featuring "Love Is Endless" by MoZella). Then a 2016 ad, "A Better Chicken McNugget" (with a cover of Cyndi Lauper's "Time After Time" by Iron & Wine.)