If you are receiving lower than expected download rates, give your ISP a call and tell them you need it fixed. If they don't want to do anything about it, look for a new ISP. Unfortunately I can't recommend anyone specific, as it depends entirely on where you are. Someone more local will need to suggest another ISP should it come to that. Consider asking friends or family what ISP they use and what the service is like. Recommendations over the internet are not the best way to go.