tablet help !!!

HI, my mum gave me this second hand tablet. all i know is its android, theres no name on it at all, the only info i have is what was asked when i registered on here, firmware/kernel. on the back of tablet ive got a model number m-001 and its made in china, thats it.

So my problems. because i dont know the model i cant upgrade/update android. It didnt come with an sd card so ive got my cameras card in there and it provides a total of 3.68gb, how much do i need to make it run quicker. its freaking slow. I dont have alot of games on it because it wont load them, not enough memory maybe?

also the lady who had it done a complete factory reset before she gave it to me so i cant download any pdf files or use an ereader app, i get the error message (no program to open document) well something like that anyway,same meaning.

Where do I start?

Post a picture maybe someone can ID it and get you pointed in the right direction of rooting and flashing a new ROM or kernel to improve performance. Although if it is a generic china android tab with out a dev community, I'd point you in the general direction of a nexus 7. Also check settings --> about phone and post everything you find there. It might help identifying your device. Good luck.