Software update 10.7

hi and thank you in advance.

i Am running an early 2008 imac with snow leopard 10.6.8 2 gig ram

i ply poker and the softwrae is updating and requires 10.7 at least IE osx lion.

i Have the system requirements just to run this but software like logic express 8 will need updating to 9.

i am concerned with my imac running at capacity with all these updates that it may effect performance.

could anyone advise me with any options I may have as I love my poker but also love making music ...

thanks

ANdy