Depends on what you are using it for. Both will kill small to medium size game within their limits.
Not always. The gun should be selected for the purpose it is to be used.
200
plenty
want ad, gun show, gun shop
243
50-200
Probably the 300 is going to give you better performance when it comes to accuracy. I sure am a fan of the 3030 as a nice lever gun though.
100-1000 USD or so
Well, it is a rifle, but dozens of companies make rifles in .243 caliber.
Mild recoil
Depends on how you define better. Both are excellent hunting cartridges for medium game. The 30-30 is an older cartridge, and in general has less range than the .243, but fires a heavier bullet, and may be a better rifle for hunting in wooded areas with limited visibility and range. For shots at longer range, the .243 will have greater reach and accuracy. You pays your money, you takes your pick.
5 lbs and up