If you're worried about her roaming the living room, an easy playpen to make is to take some grids (like the grids used to build the cages on this site
http://www.guineapigcages.com/cubes.htm) and zip tie them loosely together. With the loose zip ties, it can be folded up when not in use. The 'guinea pig' playpens marketed at Walmart aren't a great solution. Though they are marketed towards pigs, many pigs can manage to get over the short fence, and one playpen isn't really a lot of room.
If you're worried about the floor, you can use a number of waterproof liners to the pen; garbage bags, a tarp, shower curtain liner, or a painters drop cloth all work to keep any wetness off the floor. On top of the bottom layer should be something more absorbant, like towels or newspaper. The floor time pen should ideally be as big as you can make it, the bigger the better, but it should at least be larger than the cage for a good chance to exercise and explore. You may also want to put out some toys
http://www.guineapigcages.com/toys.htm or things to do for her in the floortime pen.
This link
Guinea Lynx :: Behavior has types of noises and behaviors she may exhibit, and what they mean as well as some soundclips of them.
The fleece blankets you may see in cages or floortime pens are becoming a popular bedding type. Fleece wicks moisture away, so it will always stay dry. There must be an absorbant layer underneath, for example towels, to soak up any pee. Fleece is quite a bit of work to keep clean in a cage- it must be swept daily for any poops, and changed regularly and washed. However, there's also many benefits over loose bedding.
http://www.guineapigcages.com/forum/...ect-study.html Has more info on fleece.
Staying in one place in her cage probably means she was bored there. Chances are she didn't have a large enough cage or enough things to do. There are again instructions on the main page for making a larger cage. The toys page I posted above gives ways to keep your piggy entertained and happy.