What are the "must-see" spots within Kuala Lumpur if I need to spend only a day or two in the city?

im traveling to kl on the 26 till 29, where can i catch a rock liveband in kuala lumpur?

I'll be going on a 3D/2N trip to Kuala Lumpur and I was thinking of Radius International Hotel Kuala Lumpur (Superior room) as my accommodation. Is it a good place to stay in? Is it clean? Is it safe? Is it near to the red light districts where there are hookers and pimps everywhere? Or does anyone of you have a better hotel to recommend? It must be less than RM 230 per night (approximately USD 70). And it must be in a very safe area, especially at night. Thanks.