56k is going to take a long time to do anything, so I feel your pain. What you need to do is try to download the entire 1.6 patch, then grab the 1.61B hotfix. The 1.6 patch is bigger, but it prevents you from having to update for every patch created (which is not worth the time). I think there are a few other threads on BFNation regarding the 1.6 and 1.61 patchs already, so I'll let you look at those for more info. Corrupted files are annoying, but there a part of patches these days. Here is a list of the patches that you can grab here, last time I checked they worked fine:
http://www.bfnation.net/files/patches/
You might look into getting at least the basic DSL. The price is about $2-5 more per month and the speed is about 5-10 times faster. Check around you area or google "DSL availability" to find some sites that will show you whats available in your area. At this stage in technology game, almost any DSL is better than dialup.