Microlight hire in the UK is now legal (it wasn't until a few years ago). The rules are summarised in BMAA TIL32
http://www.flybyhire.co.uk/upload/BM...032%202008.pdf
However, and its a big however, very few schools/clubs actually do it because each individual aircraft has to have a dispensation from the CAA and insurance costs are very high. To be honest you'd be lucky to find one.
Also hours flown in a microlight may not count towards licence revalidation, depending on what type of licence you hold.