Andy is right, avoid DVD cams because when you want to edit footage its a bitch. At the low end, miniDV cassettes are still the best for numerous reasons. I assume this is the format you have now.

About the noise, many cheaper camcorders suffer from tape noise im afraid but if you have an external mic socket this is good because using an external mic will get rid of the noise. Maplins do a cheap Condensor Zoom mic (£20). Ive got it, its ok for the money.

For the £150 you say you paid for the cam id keep it and get an external mic as most cams in this price range dont have that option and trust me, you will need it.

Do your reserach on here and other forums and you will understand why.

all the best

Matt