This made me happy to know that there is a chance of TES-O working with my Dial-Up...
And yes, Jonahirt is correct on this.. Actually, one of the reasons why I quit RuneScape is cause of lag.. They had a major update to how Java runs it, and such, which created much lag for Dial-Up users, like myself.
Yeah, you'll just have to download the patches elsewhere, like at a library or friend's house, but I'd be willing to bet it would work.
At first I downloaded the patch files and installed them but that was a painful process, getting the right file and doing all the work. So I bought an external hard drive and put the WoW directory on it that way I'd just plug it in somewhere with broadband, open the WoW client and let the patcher do the work. In the end it was still an enjoyable experience on dial up.