No, its probably not true. It rather depends what's actually growing in it now - annual weeds will disappear with that treatment, but perennial ones won't, and anything woody based like brambles certainly won't. Any chance you can post some photos so we can see just how much of a disaster it is, in order to give best advice?
It's a pity you moved in this time of year - May is the month when anything growing positively romps away, you can almost see things growing, its that fast, so it may not be as bad as you think...

bamboo your a star!!! im going to take a few photos now and see if i can get them downloaded onto hear thanx for the speedy response!!!

Stop worrying about how bad your garden looks, you will only make it look pleasant and to your liking in time and with hard work. Many plants growing wil be hard to clear at first. If you buy a book on wild plants you will soon learn what they are.
Getting rid of rubbish is best these days in a council wheely bin, stones can be used as drainage in a wet corner. Glass, tins, nails etc. go in the normal wheely bin. Start at one end and work slowly, clearing and cleaning your garden, don't try to do it all at once. When you have conquered this first, post again or P.M. me and I will help you get further on. Good Luck.

thanx doctorbob

Take courage and do a bit at a time - time spent now in doing it properly will pay dividends later. It makes a difference what the soil's like so could you dig a bit and see whether its heavy and sticks together in lumps or if its light and a bit sandy?

Invest in some bath salts - you're going to need a few long, hot soaks to ease the aches and pains that come with creating a new garden, and take heart - anything at all you can do will be an improvement! It's very good exercise, too, and cheaper than the gym!
There is nothing quite so satisfying as making a garden out of a wilderness, and in time you'll become absolutely hooked, and we'll all be doing our best to answer all the questions you'll have, and you'll end up with a lovely place to spend a lot of happy hours in. There aren't really any shortcuts, it won't happen without a lot of work and a few mistakes along the way (which really won't matter), but you sound like a real enthusiast, and I'm sure you'll succeed and enjoy yourself. Try charting your progress with a blog diary and pictures, and we can all enjoy it with you. Welcome to Goy, Gaunty!

Rougly how big is your garden Gaunty? Does it have lots of lawn?

We cleared a large 'rubbish dump' many years ago when young and able. One weapon was fire.....not so easy these days. Another was exporting to a skip/s....naughty but handy, and with permission too! Composting in an unused corner. Flagging down the local scrapman or asking him to come and collect any metal objects, as we did yesterday. Obviously use the local disposal facility. Bricks and old sunken paving can be used as hard core. Having a lawn will keep most perennial weeds at bay with regular cutting. Intended flower/vege beds need more care to grub out couch and bindweed. We also used a bulldozer hired by neighbours, doing same as us. That was to smooth out about 1/3 acre between us and bury huge chunks of dumped wall etc really deep down. Cheer up it will get done and it will look good.