Your best option would be to have Afrihost manage your Telkom account for you - Telkom is useless when it comes to customer service.
If you are the only person that is going to be using the line, for browsing, emailing, Facebook etc. then a 2mbps ADSL line with around 10GB of Cap should be sufficient.
If, however, there will be an additional user in your household and you'll be using/updating your cellphones while surfing/streaming/gaming then you should look at packages like 4mbps with 50GB of cap and up.
It all depends on what you'll be using your line for and how often you'll be using it.
Also, in my honest opinion, uncapped packages aren't worth it, especially now that Afrihost gives you uncapped evening data.
Please give us some more information so that we can better assist you :D