are registry cleaners good for my computer?

i bought a vista in may and have quite a good deal of installing various software and sometimes it starts to freeze and say not responding. should i use a registry cleaner?

Yeah very good. They clean up stuff like software fragments, broken files, cluster, unused items..you name it.
CCleaner is one of the best out there. Your machine benefits as well in terms of performance.
You can also try Tuneup Utilities..works really great on my computer. http://www.tune-up.com/products/tuneup-utilities/