kaycie....not sure exactly what your ailments are, but (and this may sound too simplistic) I would think you need you need to list what you hope the surgery will accomplish if it goes perfect and then what you will accept as a minimum (in other words what is the minimum result that will make the risk worth it)
Once you do that you might want to discuss it with your doctor and...repeat "and"...the surgeon (surgeons and the primary docs do not always agree on potential outcomes) ask them if you are being practical...ask about long term results....ask about future treatments, options and surgeries.
For me I didn't suffer with major massive pain each day...I just started getting partial blocks on a semi-regular basis and those are very painful. I also felt nausea most days. Things got to the point that very soon I would rupture so I chose surgery....my doctor agreed, but he also kept saying that surgery was the LAST option.
I do not understand the idea of doing surgery once the steroids quit working ...obviously that statement is tied to your specific symptoms....I have not done steroids of any kind (by choice) in over 5 years. I just won't do them.
I understand your fear of Tysabri....but you may want to review your choice in that...surgery is certainly not risk free....there may be a more direct and immediate risk or danger with the surgery than there is with the drugs. The dangers with tysabri seem to be linked to several other drugs so you may not be in as much danger as you think. Also the negative reactions seems to be found more often in the MS patients than with the crohns people....that indicates to me a reaction to the drugs more widely used in the treatment of MS. If I remember correctly there were no deadly adverse reactions until the MS trials. I was on Tysabri for almost 2 years during open label trials
Lastly.....I have been told by three different gastro's and my surgeon not to expect a cure from the surgery....crohns will always be there unless of course they remove every part of the digestive tract including my throat, mouth, and so on.... Maybe one surgery is all I will need...but it is doubtful...and for some it seems that once you go down that road you have to get back on it fairly often.
Just another POV....you have a tough decision to make...good luck