Kartik,
Let me give you a textbook answer. For reference, this info comes directly from the book "Firewalls 24seven" by Sybex press.
Checkpoint Firewall-1 Major Feature set:
1. Stateful packet filter
2. Protocol specific content filters (HTTP, SMTP)
3. NAT
4. VPN firewall-to-firewall and firewall-to-remote client
5. User authentication handled transparently throught the various protocol content filters
Some of the minor features:
1. Policy-based configuration and management
2. Content vectoring protocol (Lets you strip e-mail attachments, block URL's, etc.)
PIX Major Feature Set:
1. Stateful inspection filter
2. NAT
3. Authentication
4. VPN
5. Probably the fastest firewall on the market
6. Support for external security proxies and content filters
PIX Minor features
1. High availability
2. Support for four security zones
3. Java filter.
Just to add one thing -- I have used both software firewalls and now have a PIX. I will never go back to the software firewall. The PIX is quite a bit harder to configure (lack of GUI, you know), but I like it a lot better (SPEEEEEEED).
Hope I have helped a little.
