Sluggish performance and engine light - added new plugs and oil

You need to check for engine codes to see what is wrong. Bring it to a parts store for a free scan for codes. The check engine light indicates a problem, probably the emissions system, which is causing the poor performance. The parts store will plug a hand held scan tool into the cars diagnostic port (usually located under the dash) and 'read' any codes stored in the cars computer. They can them tell you what code #'s come up, what they mean, and how to correct the problem. If you have any questions after that, post them here w/ the code #;s for further help.