Thinking of upgrading my laptop and wireless.

My wireless router is a 802.11 B/G was reading tonight that this is very slow and an upgrade will improve things?????
My question, Is it better to do a router upgrade first then get a new laptop or laptop then router upgrade. Does it matter? Just a little nervous changing my router. Never had to change one out before. What will I need to know before doing the changeover?

Laptop I think I know what I want. Looking for recommendations on brand and place to purchase from. (windows) Kinda like to buy local but on-line is not a problem if the deal is right.
Local is most all stores. Staples, Office Depot, Office Max, Best Buy. HH Grieg, Wal- Mart, Target, Micro Center. Etc.............