Question about shipping First Class

I want to ship a 5oz Xbox 360 game in a bubble mailer. For shipping First Class eBay gives the options large envelope ($1.78) or package/thick envelope ($2.83) which should I choose?

If I go to the USPS website and choose large envelope, they asks if its rigid. Choosing rigid treats the envelope as a thick envelope and gives me the $2.83 price. I see sellers on eBay using both choices almost 50/50, but shouldn't everyone use the more expensive choice since games are rigid?

Also PayPal costs .23 less for the package price, do they or anyone else offer a discount price for first class large envelopes?

Any tips for larger special/limited edition games? Like larger bubble mailers or small boxes?

Thanks for any responses. I haven't used eBay for about 15 years. I want to avoid any issues while I try to build reputation.

A large envelope would be like shipping documents in a manilla envelope. The reason why there's a diff is to account for the added time a mail carrier needs to drop off a package (anything really thick or rigid) at your door vs can leave it in your mailbox. 

If you're shipping a game, yes, it's a package. You can risk shipping it as an envelope but I think the USPS can either return the package to the sender or charge the recipient. 

For heavier items and CEs, you pretty much have to use a box unless you wanna risk external damage. If you're lucky and it fits in a Priority Mail flat rate box, that's usually the cheapest way to ship but it depends on a lot of factors. People used to send large/heavy CEs via Media Mail but I think the USPS cracked down on those (video games do not quality for Media Mail). 

Choose package / thick envelope. Large Envelope is for well, large envelopes. If the item is 2/3rds of an inch thick (like a CD or DVD case in a padded mailer), it goes up to package automatically.

PayPal (or eBay if you're sending something you bought, along with other similar online postage sites) is the only way you can get a discount, USPS' online shipping tool doesn't offer it anymore.