First, let's do the math. 56K connection likely runs at 40-45ish (56K is a theoretical connection, by FCC regulation cannot exceed 53K due to electrical limits on the public network, in the real world usually connects in the high 40s and actually operates at somewhat less due to variable line conditions.)
You say there are up to 6 computers connected simultaneously.
So when everybody is hauling, 42 divided by 6 is 7Kbs of bandwidth per user. Yup, that's pretty slow. Even when the instantaneous usage of the bandwidth moves around between users as their individual needs vary (such as a few milliseconds fetching a page and a few minutes reading it), there is still a lot of latency as the various requests queue up for the limited bandwidth.
Getting a router isn't going to change the math by much. I presume you are using one computer with some sort of proxy sharing (such as Windows Internet Connection Sharing), and a dedicated router might improve things very very slightly because it is more efficient due to the computational overhead of a computer. But that is not going to be night vs. day. Furthermore, dialup connections on a router are rare - usually this is an additional feature on business class routers (i.e., expensive) to provide fail-over capability in case of interruption to the primary broadband service.
At best, you might consider some performance tuning on the individual systems (setting MTU and RWIN to appropriate levels for congested dialup) or one of the web accelerators (which use page compression and server cacheing to feed things a little faster, but are really only useful for general surfing, not gaming, and are usually proprietary to your ISP).
dw
Hello, I have a 6 networked computers through a switch but I connect through the internet only with a 56k modem, so when all the computers are running and connected through internet my connections is very slow! How can I improve my internet connection? Somebody told me that a router could probably improve it. Is it true? How?

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