Is there a way to use other marine weapons when fighting the queen and actually kill it without blowing it out of the goddamn airlock? Would the level end and cutscene trigger in that case?
Yes, there are two ways to do this.
1) Enable debug mode by doing this: find the game in your Steam Library, right-click, go to Properties, click Set Launch Options and put in this code: -debug. Then when you're in the game, open up the console by hitting the talk button (default button is this: ~), delete the word SAY, and then type GIVEALLWEAPONS. This should give you more than what you need to kill her. If you need more assistance, you can enable godmode by typing in GOD into the console. Killing her won't trigger the cutscene because you're in debug mode, but the level will end once she's dead.
2) I also made a weapon continuity pack that provides the weapons that you would have gotten in the previous maps at the beginning of each successive stage, so the Hangar level starts out with all weapons. Once you spawn in, you'll have to turn around and pick them up, but you can use them all the same to kill her. This will trigger the end cutscene because the game is not in debug mode, and it may also give you some funky stats. You can download the pack here (it comes with installation instructions): http://www.moddb.com/games/aliens-vs-predator/addons/weapon-continuity-pack