Just about all the cooling pads will help. As for extended warranty, I have a very different view than most. I prefer to be "self-insured" based on the following.
The extended warranty is very profitable for the seller/OEM. Therefore, it may not be such a good deal for the consumer. Of course, this is based on statistics, and most consumers don't think that way. Usually electronic equipment has what's called an "infant mortality rate." Infant mortality is failure in the first few weeks or months. If it passes infancy, chances are it till run a long time unless abused. Statistically, the extended warranty will rarely be used or exercised.