I missed a bunch of episodes myself, but from what I gather, the current storyline that YTV plays is on Fridays at 9 (pacific time for me)....the rest of the episodes that they play during the weekdays are repeat episodes, so you should probably watch those ones, as they go back quite a bit, so you can jump on there.
But anyhoo, here's a quick (and real shoddy) sum up of whats happening on YTV right now:
The new characters are called "The Band of Seven," who were a bunch of evil warriors from way back in the day, terrorizing the country and whatnot, until one day they were all killed. Flash forward, and they have now been resurrected by the Shikon jewels, and are killing everything again. Pretty much each episode just fills you in on each of the seven warriors, and they keep attacking InuYasha....then the band of seven gets the idea to go kill Naraku, and a race is on between the band of seven to obtain more jewel shards than the other, so they can take on Naraku. The last episode you saw, only three people were still alive from Band of Seven (the others had been killed, and the shards were equally in possession of the surviving three). In that episode, the other two were killed, and all the shards are now in the possession of Bankotsu, the leader of the band of seven. And now he wants to go whoop Naraku.
A very very useless summary of what is currently happening. But since you missed alot, I would be here typing for hours if I went in to super detail, so I'm simply trying to sum up what they are doing at the moment.
Naraku is hiding in the cave trying to gain more power, which is why the barrier was around it. The barrier was being held in place by a dead monk, who had been tricked by Naraku into creating a barrier around the mountain, but Kikyo showed the monk the truth, that Naraku was using him, so the monk let down the barrier. Now a whole load of Naraku's demons have been set free from the mountain, and everyone is booking it to try and kill him.
My suggestion is to look up an episode guide, and just read all the summaries from the episodes you missed...it'll give you a better idea of what's happening.