*will a celron 2.8 ghz D335 cpu be able to cope with dvd burning storing tv to hard drive.
Easily - but be careful that the motherboard can use Celeron D processors - read the manual.
*i have 3 slots for ddr400 ram 2slots have 2x256 what size memory can i put in spare slot?*
The manual will tell you.
*anyone know minimum specs for to things run smoothly Thanks*
The Celeron with 512Mb will run very smoothly. What graphics card are you thinking of?