To find out the size:
Alternate-click on the folder you're interested in, and choose Properties. The Properties box should tell you.
(Or you can go to the parent folder in Explorer, then change to detail view - the size should be listed in the right-hand pane)
Check to see if data is stored anywhere else. I'd recommend looking at the size of the whole profile, which will also include anything on your desktop &c.
Some errant applications might store your data elsewhere - for instance, the software you use to pull photos off a digital camera could try hiding "albums" somewhere deep in C:Program Files.
Can these be saved to a CD?
If you have a CD
writer, and if no individual item is *really* big, it should be easy.