If you dont want to spend a lot of money on all brand new equipment, I suggest something like an Athlon XP 1800 perhaps. Quite cheap, but still a good upgrade from what you currently have. RAM is cheap too (make sure you get a type that your system supports though, no good getting DDR 3200 or something if your comp only supports SDRAM).
You’d need a new motherboard for that processor, but thats a good thing. You can get one that perhaps supports better RAM (dunno what you have now) and AGP (again, I don’t know if yours does now or not) so you can get a better vid card. Again, if you go just for what you need, not the most expensive stuff with al the features, you can get a reasonable mobo pretty cheaply too.
You can get a decent graphics card for around $50 now too. I’d reccomend a Geforce 4 ti 4200 though, card isnt bad at all (It’s what I have at the moment, and this and other more graphics intensive games run absolutely fine with it. I havent had a game yet where I’ve needed to turn the detail to low and turn loads of crap off in order to play it) and its not that expensive anymore, due to the release of the FX cards, so it’s good value for money if your on a budget.
The reason for this post was just to let you know that you dont have to buy the best, most expensive stuff if you want to upgrade.
You could get a nice upgrade on your current machine for relatively low money compared to buying all top of the range stuff, and get nice FPS in ET and other games too.
I dont mean to sound patronizing either. I dont know how much you know or dont know.
In the end, its still money, depends if you have it. I’ve always got too much month left at the end of my money 