I installed Windows 7 on a Dell Inspiron 1525 this weekend. It took less than 30 minutes with a brand new 640GB drive. Everything went nearly perfect – the only drivers that Win7 didn’t install was for a “Base System Device”, which was the Ricoh card reader. Here’s a direct link to the correct driver:
Remember to always backup your data before installing a new operating system. Also, there is no direct upgrade path from XP to 7 so you will be starting out from scratch with software installations, etc.