I'll try to be as nuetral as possible.
It wasn't hard to recognize Jon for who he was, but Garfield was done lazily.
Voice-acting...well, it is not as if the original show is on anymore, so you probably had nothing to base an imitation off of. Still, it could have been better.
Animation...not the best I've seen, but your reaching the best I've seen would probably take ALOT more experience than you've got. (Judging by the amount of videos you've posted). Try to keep the limbs below the screen's edge when you haven't fully connected them to the body. Doing so elicits less complaints from people.
Coloration...lazy, but not outright terrible. Lines on Jon actually were not bad. On Garfield, however, had WAY too much black for his expression when he ignored Jon and ate the lasan- oh screw it. when he ate the food. Take out a handful of the lines.
Sound effects= Fitting, I guess.
Setting= Garfield and Jon live in a sort of...what's the word the crappy live-action movies used? (I don't recall, so I'll use something else.)
A neighborhood Development. There would have been other houses nearby, and a fence encircling the house if not a neighbor's house on the left and right.
Story= If not for where Garfield flipped him off, would have been fitting.
overall, on the scale of 1 to 10, I've give you a *See star rating*. My reasoning for this is that I think you actually tried, otherwise you'd have done this the way Fatbadger did his movies. Which is to say, you've have given it a title that fans look to expecting something at least mildly interesting, then made some random shit up to mock and insult them and probably hurt their ears, and maybe give them a seizure if they're sensitive to flashing lights.
While I didn't actually LIKE it, I did not hate it. When your skills improve a bit (if you have the time) redo it, and re-post it, and I'll give you a higher rating.