Hi there Jessica
A few points to feedback to you from your post there!
1. There are 'many places to avoid' in EVERY town and city, and not just in the UK but worldwide! - It's an incorrect assumption or statement to say 'you need to avoid an area becuase of the areas you've heard about are bad' - Manchester has MORE better areas to live in that bad, same goes for any other town or city. Is it fair for example to say 'avoid living in Detroit because there's many bad areas'? - no, I have family who live in the outskirts of Detroit and their areas were extremely nice and safe!
2. I know people who live in Nottingham, been there all their lives too - it IS a nice place, and yes there are certain areas to avoid and yes it has had some negative aspects due to gun crime recently, but in the general picture of things you dont have to worry about that.
3. Manchester has more opportunity than Nottingham- it's a much larger city! You don't mention what kind of jobs you are looking for and in which industy or sector, but if you can change locations from Macnhester to Nottingham just like that, maybe some reseacrch into the best places overall in the UK to go for those jobs?
Have a look at upmystreet.co.uk and rightmove.co.uk for getting more information.
Hope this helps !
Cheers DtM! West London & Slough UK!