I just edited the first post, note the bolded line about performance. I included that to curb problems with people getting excited and not noticing the system requirements. UC is huge, you'll see. Tweaking settings can have a big impact on performance so you might be able to squeeze it in that way if your PC isn't great.
It often appears to hang at a point 20-30% into the process, which is normal. Anushka says it's probably loading lots at that point.. you should be just fine with a little patience.