1) We could defeat those guys easily with today weapons. The St\T guys (and gals) are fairly fanatical and not afraid to die, but they are basically stupid. They use massed WW1 style infantry attacks with little recon, manuver or fire support of any kind. One on one, they are no better than our soliders today, reasonably competent singly, but in mass, they fight like its 1799. Im going by the movie verion and not the book-fyi.
2) Im assuming you mean the WoWT aliens and there shields. We only ever see there shields defeat conventional weapons, artillery, missles etc. We have no idea if there shields also offer protection against directed energy weapons. Since kinetic weapons are totally useless vs them, I would say at least 100 years of non-stop refinement of ground and air-based laser weapons. And even then, simply have no way to know if even then that would be effective.
3) Been to long since I played that, but I dont recall there tech being all the wonderful. Just more efficent in terms of deployment I think. We could probably beat them. Unless they do the dreaded zerg-tank rush. We take way too long to make tanks and other weapons systems, and as time wears on, we get *worse* at cranking out weapons system in a efficent and timely manner-dont expect that to magically reverse itself anytime soon either
4) No idea
5) If the idea is there just sit back and nuke us from orbit, wed lose. At this moment in history we have no resources to spare for mass off world development and I dont expect that situation to change much even in a centurty from now. If they decide to invade. We have plenty of AP weapons and ammo that can be carried by individual soliders, so I would expect the clankers to be formidable but not unbeateable even with todays weapons. Depends on numbers, but we wouldnt need any radically new tech to take them on. There air-support is another matter but Im also going to assume our conventional jets could destroy raiders, but thats an unknown. There speed would be the real advantage vs our jets, if that would be critical or not I cant say.
6) Too much magi-tech. But one the ground, the UFP are even dumber and more useless than the Federal army of ST. We have ranged artillery, mortars, RPGs, body armor, long-range sniper rifles, ground attack aircraft and so. All the UFP has are there phasers and there pajamas and there feet. Our guys now can hump it for hours in a hot desert with 60pds. of gear and ammo on there backs, then drop it and fight for hours after that. Your typical UFP 'security dude' cant handle anything outside there climate controlled bubbles and then only for short periods of time. Yes, they could inflict some causaulties with there ray-guns, maybe even damage or disable some vehicles, but thats about it. From space, forget it. Too much fantasy tech that no amount of R+D in our universe could overcome. But we could stop them easily now on the ground. In fact, theyd probably regret trying in a real hurry. Without there magic starships to vaporize things from orbit, they'd be butt-stomped,fast.
7 No idea
8 Hard to say, killing a borg isnt that hard, what you really need to do is take a low-tech approach. Edged weapons, blunt objects, even our guns and bombs would probaly shred them easy. We dont use hokey energy guns so there shields would be useless. Again, no real tech advances need to defeat them in single combat. The borg are slow-moveing, use no ranged weapons of any kind, they just sorta shuffle along. And they rarely seem to exploit there instant comm ability in any real way. They just keep shuffling at you until they are destroyed or win-hardly tactical geniuses. Where it gets tuff if they start borging up say, communcations and other things wed need to co-ordinate a defense. That could be tricky, If we had truely de-centralized phones and data networks, that might help. But again, borg-nano tech is kinda magiky so...
Rest I have no idea..