Robotics Package purchase advice

Hi Experts,

Need your Advice
Years before, i was a programmer slowly moved to Management and this is my serious attempt to have this hobby and reconnect to logics.
My requirements:
Software:
Programmable preferably C and could also take in Python scripting and it should support multiple languages and GUI support. Ease of programming and with well defined blocks and API calls defined.
Hardware:
Relatively Advanced Processor, i should be able to debug, which uses RTOS so that i could create some threaded, priority programs.
The hardware which allows me to add blocks new hardware expendable and configured,

The functionality i am looking is basically, visual interpretation (something to do with Camera attached and visual procession, audio responses and movements )

Please could you guide me to the right links or please say it, if i am taking rubbish, if so accept apology for i am naive but i have interest to pursue. My budget is ~500 USD.
Inclusive of Software and Hardware.

I would be really great, if the product suggested has a great support in terms of technical help, forums and compatible hardware extensions.

Thanks in Advance
--Anand