Okay, so I have a question: was the ending really that bad? [...] does it really ruin the entire series like I've heard?
Alright, I'll try to hold back.
The first Mass Effect game is wonderful. It does such a great job at world building that it will leave you wanting more. Yeah, it's by no means perfect. The combat doesn't measure up to traditional first- or third-person shooters, the items menu was horribly unorganized, and assets were overused, but overall it's a great game.
Then Mass Effect 2 came out. Combat was refined, but the RPG elements took a hit, unique elements were removed or changed, and they attempted to fix problems in such a way that made things worse. The items menu (where you hold weapon upgrades) is a mess? Okay, eliminate weapon upgrades. Some people didn't like the driving segments with the Mako? Replace it with planet scanning. The RPG elements look overwhelming? Dumb it down. On top of that, the main story takes a back seat to several smaller character stories that are great for character development, but ultimately makes the plot of Mass Effect 2 meaningless. It doesn't deal with the main issue brought forth in ME1.
Finally Mass Effect 3. Combat is again refined so it now resembles a traditional third-person shooter more. Weapon upgrading is back and actually really good, and certain RPG elements are improved from 2. Certain missions, specifically the ones on Tuchanka and Rannoch, are some of the best in the series. But the dialog wheel suffered more detriment here, side missions are an even bigger joke than previously, there were a lot of cut corners, and then there's the ending. The ending failed on so many levels. It introduces a new character and a deus ex machina. There are three distinct choices that determine the end of the game, and each choice is terrible. The entire game has made a point of undermining each of these three choices. All the work you did up until this point means squat, really. There are slight variations in the cut scenes, and one ending can have an additional scene, but ultimately your choices didn't matter, which is important since the series sold itself on your choice mattering.
I won't say Mass Effect is terrible. I actually love Mass Effect. But not blindly. If you want to get into Mass Effect, I won't stop you. Hell, I'd even encourage you. Just keep in mind that while each game brings great things to the table, it will end in such an unsatisfying way, that even now people still are angry with what they were given in the end.
Oh, and the Leviathan DLC was garbage. It explained things, yes, but I was better off never knowing. Oddly enough, the ME3 multiplayer is damn good, and I'd still be playing it now if I had Xbox Live.
Sorry for derailing the thread. Back to topic.
shooter on coin ops wre the same, bang at least a two hour run on one coin, tooled up to the nines, wipe out all in your way, then enter name for highscore, NO outro. 
The only reason I wouldn't count those is because I didn't get invested in them story-wise. Otherwise I'd throw Link's Crossbow Training in there. It ended so soon and without a proper final boss.
