You're probably on their 2mb package, which should translate to download speeds of 240Kbps and 60Kbps uploads (at best). Very odd figures returned with your speed test - which site did you use?
Regarding download caps;
* M tier users who download over 350MB will have their speed capped at 1Mbps during peak
* L tier users who download over 750MB will have their speed restricted to 2Mbps during peak
* XL users who download over 3GB in peak hours will have their speed restricted to 5Mbps
Your speed is restricted for 5 hours or so if I recall.
By the sound of it you're on the M package.
More info here; click here
There are a few steps you can take to ensure your system is set up for the best speed. I take it you're using ADSL broadband (connects to the phone socket), not DSL (cable).