Methodists typically are a bit more liturgical than Baptists. Infant Baptism is practiced in Methodism while Baptists reject infant Baptism. Baptist churches, historically, are autonomous; Methodist churches historically adhere to a kind of episcopal polity (how the Church is run) known as connexionalism. Methodism is historically Arminian, Baptists can fall either in the Arminian or Calvinist camp, with a number adhering to a mish-mash of both. Methodism generally has what's known as the Wesleyan Quadrilateral (Scripture, Reason, Tradition and Experience as a four-footed way of theological reflection, Scripture being most important); Baptists vary in their theological methodology.
Really, however, the biggest difference may be, apart from the issue of infant Baptism (and not all Methodists practice it) the big difference between Methodism and Baptists is that Baptists are a very diverse, scattered bunch with only a few key "distinctives" that makes the Baptist tradition cohesive; Methodism is a distinctive theological tradition with a lot of central ideas. There are probably more Baptist denominations in the United States alone than any other denominational family.
Free Will Baptists, Primitive Baptists, Southern Baptist Convention, American Association of Baptists, General Six-Principle Baptists, Old Time Missionary Baptists, Reformed Baptists, Cooperative Baptist Fellowship, etc, etc, etc.
-CryptoLutheran