I need to resite a well established rose bush, how do I do this?

Firstly, try to move the rose as soon as possible while it is still fairly dormant. If you can't do it soon then you will be better off waiting until the autumn to move the plant.
First you will have to prune the rose right back to about 1 foot at the most. Don't worry.....It should respond well to the pruning and it is very difficult to kill a rose from a hard pruning. You object is to make the rose easy to handle and Peace roses have some wicked thorns you don't want to be messing with.
Prepare the planting area for the rose's new home. It should be in an area that gets at least 6 hours of full sun a day for optimum flowering. Dig a hole which is larger and deeper than you expect the root ball of the existing rose to be. To the bottom of this hole add some nice, well rotted manure or compost. Also...now don't laugh at this, it works.....throw in a couple of banana peels. Add bone meal too. Mix all that up in the bottom of the hole.
After 28 years the rose will be difficult to dig out. It will have a huge roots system which probably goes quite deep. Dig as big a root ball as you can manage to handle. You will end up cutting through roots I'm sure. If you have a fair distance to move the rose and it is going to be out of the ground for longer than a minute or two then wrap the root ball in some moist newspaper. Keep as much soil as possible around the roots.
When you plant the rose into the new hole, site it so that the level of the soil will be about 1" higher than it was in its old home. In other words, plant it 1" deeper than it used to be. Place the rose in the hole and fill the hole about half way with soil. Now you want to fill the hole with water and let it drain away naturally. This will settle the soil and eliminate any air pockets under the root ball. Once the water drains away continue filling in the hole and gently firm the soil around the rose. Mulch the rose with compost or leaf mould keeping the mulch away from the rose stems. Make sure the rose is watered daily for the first week or two. After that keep the rose moist but not soggy for the first year. The rose should start to put out new shoots within a couple of weeks.
Rooting cuttings from roses is a bit hit and miss. Some types root easily and some are very difficult. The best time to take a cutting is in the spring. Choose a cane that is either just about to flower or has just finished flowering. Cut about 6 or 8" of cane about 1/4" below a leaf. Remove the bottom leaves and trim off any flower buds. Dip the cane in rooting gel or powder. Push the cane into soil in a pot or in the garden. Cover the cane in the pot by placing the whole pot into a plastic bag and sealing it. If the cane is in the ground then cover it with a large jar or plastic pop bottle with the bottom cut out. You will know the cane has rooted when new grow appears on the top. Make sure the cutting is out of direct sunlight. It needs a warm bright place. Light shade outside is the best.

thanks for the advice, i am a real novice, the garden was always my Mum's department.... I will try taking a cutting first, as I dont want to risk losing the whole plant...
Thanks again

Marguerite is correct in saying that Peace is grown on rootstock. You will probably find that if your cutting does take (Peace is a tough one to root) that you won't have a strong robust bush like you have right now. The rooted cutting may produce a much weaker plant although the colour of the blooms and fragrance should be the same. However, you can still buy Peace rose bushes. The variety is still very popular.
It was developed by Meilland and was introduced to the world the day Allied forces claimed Berlin, and on V-E Day, May 8, 1945, being presented to all 49 delegates at the very first United Nations Conference. It also received The American Rose Society’s first Gold Medal the day the peace treaty was signed with Japan.
So, this rose has a very impressive history. "In 1939, a young and gifted French rose breeder, Francis Meilland, discovered a remarkable rose he had nurtured from a single seed. Realizing the beginning of World War II posed threats to the flower’s fate, Meilland dispatched seedlings to growers in Italy, Germany and the United States."
A more detailed account of this rose is at this website.....
http://www.gerbera.org/the-gardener-2005-06-Peace-rose.html

Thank you both for the advice, I've been out this morning and had a good look at the rose, It has green shoots already and yesterday was the first fairly warm day we've had! The bush was cut right back for the winter, I asked a neighbour to do it, as i really have no idea, and do not want to risk harming a plant my Mum succesfully kept for 30 years!
I'm going to follow advice and wait for autumn or possibly even next spring before I attempt to do anything other than prune or take cuttings.
I had not heard the history of this rose in the terms as above, My Mum told me the personal history of the rose we have, It was given to my great grandmother, by her husband many years ago for her birthday, as it was her favorite flower... quite romantic really.- and lovely that it is still flowering every year all these years later.

Put it this way Gilli, yr rose bush is 1 year older than I am!!
Its funny, for years my Mum told me what she was doing with her plants in the garden, she died in June, and now I really wish I had paid more attention! I have done little more than mow the lawn in all the homes I have lived in, and now I have the responsibility of keeping my Mums garden alive! Last summer her roses bloomed right through to October, it was shocking to see,as they have normally stopped flowering by that time, I wondered if that ws because I kept cutting them?( to leave for my Mum at the cemetary)
I have started work on the garden today, just a general tidy up, but I really want to put my own stamp on it, but use all my Mums plants...
I am sure you will see much more of me on this site throughout the summer,as more questions arise.
Thanks again for sharing your knowledge on the history of this lovely flower, I will make sure I tell my daughter the story of the "Rose of Peace".