Every time I do a Coli run or just grind with other people when they use a skill i get this really bad lag and it sometimes causes me to disconnect. Was wondering was there anyway to fix this or is it just my computer
That's just normal lag, it tends to manifest itself that way because it's what you notice. If you're playing solo you actually have lag too, you just don't really notice because there's no frame of reference to compare it to.
You can try the stuff in the lagging section of this thread: