Mixer/Software Suggestion

Currently all I have is a 2kXL and a Yamaha Keybaord, I am interested in getting a mixer and a Program to record and edit. I do not know how many channels I should have or what kind or mixer I should get for this setup for what I want to do, or what program (Cubase,Ableton,Logic, Etc.) I should use(I do not have a MAC). I do not know if there is an impotant relation between the mixer and software being used together, but before I spend any $$ I want to clarify this. I appriciate any help or suggestions. Thanks

If you are on a budget get the pro tools 001, if you got cash flow get the pro tools 002. Everything you need to record in a package, industry standard, flexibility.
001 version used to be the standard before 002 came out, and it's still sick. You can get one on ebay for under 500.
Also don't forget to upgrade your comp. 1gb ram, p4, 7200rpm and higher HD, etc.. etc..

If you can't afford non of the above.. look into hardware multitrack recorders.