It is pretty rubbish atm imo. However with iTunes 11 supposedly around the corner (if they don't delay it again -.-) this November we may have an iTunes that is actually pretty good.
As for fixing iTunes crashing at random times, you need to remember if you have a lot of music, books, apps etc... Your computer needs to have a decent amount of RAM in order to expect to not crash as I remember running iTunes on a PC that had 512MB of RAM, so slow... I now have 8GB of RAM and iTunes doesn't crash but it is still slightly slow.
I'd wait until iTunes 11 comes out, if it still crashes a lot and the iTunes reviews say it is fast you may need to consider buying more RAM/upgrading your PC if it turns out your PC crashes a lot with other programs that are fairly large in size such as Adobe CS6 programs (Photoshop/Dreamweaver).
However I'd only consider upgrading my computer if it is quite outdated, I wouldn't just do it just for iTunes LOL.
From experience I know Windows Media Player is reliable.