ok maybe that is a bit Expensive, you could get one for about 100 that will be OK , but you need a new Vidcard , i had a geforce 2MX it was a great card but Ive had 4 since then and i don't upgrade very often.
If i were you id look at getting a ATI 9200 or a Nvidia 6200
Make sure its AGP and get the Best you can Afford
But Video Cards are Expensive , when i got the Geforce 2 it Was Selling for 256 Pounds (Thats Saying some thing Pounds don't Exist any more)