Your PSU should be replaced with a high quality brand with a minimum of 350-400W. If you plan on upgrading your video card at all, I would go with a 400-500W.
This post is good reading before picking your new PSU.
A couple I would recommend at minimum:
FSP 350W $30
Sparkle Power 350W $35
If you plan on upgrading:
Enermax 535W $75
Antec 550W $80