More lag than even I can take

[doggypwn]

I'm using an old pentium 4 windows XP toshiba laptop. It's almost as old as I am, and currently has been reformatted so I could use it without it freezing and overheating every 10 minutes. I also just finished a disc defrag, which helped considerably. My connection is always at 54 mbs, which I don't think is really that bad. And my computer describes the connection as excellent, so not that. My graphics card is an ATI RS300/RS300M Accelerated Graphics Port. I've been able to run minecraft pretty fast before, I think the main problem is weather now. It just causes lag because it's everywhere.

EDIT: I think that's my graphics card, I'm not good with navigating the systems on this computer. But from what I saw, there's nothing else with the label graphics on it, so yeah.